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Rho Hybrid + Atom Heavyweight (aka AR) + Beta AR.
I own all four Betas (Beta AR, Beta, Beta LT, Beta Lightweight) and both Alphas (Alpha SV, Alpha) that were released for Fall/Winter 2023.
I love hiking, skiing, cycling and running with my Beta AR. It's probably my all-time favorite Arc'teryx hardshell. It layers perfectly with my Atom Heavyweight (aka AR) and Proton (aka LT) as well. I also like the DropHood better than the StormHood, mostly because I don't use a hood that often. I find the collar to be extremely comfortable. I also love the Beta AR's pocket placements and pocket sizes.
When I'm skiing with lots of items inside the pockets of my Proton or Atom Heavyweight, though, I do tend to wear my Alpha (aka AR) or Alpha SV more than my Beta AR. I think it's because the Alpha line offers chest pockets instead of hand pockets. I just don't like all my pocketed items bunching up around my waist.
I also tend to ski for long times (six-plus hours) once I'm in the mountains. When I'm riding chairlifts, I find chest pockets more convenient with easier access to their contents. They also feel safer to me for smaller items because it's easy to drop something from your hand pockets (although I've yet to drop and lose anything off a chairlift).
One super nerdy detail to note: When wearing goggles it's more difficult to see chest pockets. But because I only need to operate with them when I'm sitting or standing still, I take off my goggles.
I believe all Beta AR, Alpha (aka AR) and Alpha SV are great for these reasons. They're also the only Gore-Tex Pro items in here, so they have the edge over the others in terms of wind and water resistance. Gore-Tex Pro means zero wind penetration even when I'm moving fast while cycling or skiing.
I wear my Beta LT and Beta Lightweight the least. Truth be told, I almost always reach for my Beta AR instead. I suspect it's because of the premium Gore-Tex Pro membrane on the Beta AR. I also find the collar and zippers on the Beta LT and Beta Lightweight to be less convenient. If I didn't own the other 3 superior models, they's suffice just fine.
The base Beta is a strange item but I do wear it pretty often. It doesn't offer pit-zips and it fits very trim. When it's not that cold but I need wind or water resistance it's feels like the perfect choice. I should note that I also own a Rho LT Zip Neck in Edziza (https://arcteryx.com/us/en/shop/mens/rho-lt-zip-neck) so the color match also makes for a nice pairing.
Overview

Winter '24 colors.

Gore-Tex Pro items. The Alpha SV is an absolute unit of a jacket. Extremely stiff and robust. It may be overkill unless you plan to wear it almost weekly for decades.

Gore-Tex items. There's a horizontal "band" or "tape" like lane that passes through the middle and cuts the Beta LT in half. One more photo down below in this write-up. I think it affects its looks.
- There is also the women's-only Beta Coat. I don't have much information about it.
- The primary insulated option is the Beta Insulated. The warmer option for men is the Beta Down Insulated (offers 126 g of 850 FP down in addition to the same 80 gsm synthetic fill in Beta Insulated). For women it's the below-hip length Beta Insulated Coat, which offers 120 gsm reinforcements in addition to 80 gsm synthetic fill.
Sleeves of all are too long, but that's intentional. They're meant to cover your entire arms when they're up. So don't size down.
Nobody dislikes too long sleeves more than I do. In this case, however, I love them because all offer velcro cuffs for easy adjustment, unlike the softshell Gamma line.
More on Gore-Tex:
Keep in mind that Alpha line is centered around climbing and alpine activities whereas the Beta line around versatility.
Verify the source to this on Arc'teryx's own Naming Scheme Page here, for both Alpha and Beta, as well as suffixes such as LT, AR and SV.
Canberk is 5'11" and 165 pounds, with an athletic build. Size Medium fits him perfectly across almost all brands and product lines.
Arc'teryx Alpha vs Beta: Typical buyer profiles

Horizontal line that goes through the Arc'teryx Beta LT.
"I want to stay active throughout the winter. A lot of winter hikes, outdoor hockey, skiing, cycling, climbing and more; as well as everyday use. I don't expect wearing my new jacket for 10+ years. To me comfort is more important than durability."
Beta, Beta Lightweight or Beta LT is your jacket.
I'd base my decision just as much on the looks and color as on the performance.
Here's how Arc'teryx compares these three: https://arcteryx.com/us/en/compare/X000007725/X000007726/X000007301.
All of these are 3L Gore-Tex but Beta offers the least thickness of 30d in comparison to 40d thickness of the other two.
Beta LT is the only one of these three that offers a tricot backer instead of a C-Knit, which is more durable but also less breathable, less stretchy and less comfy.
Lastly, if you have no plans using these jackets with the helmet, then take a long look at the Beta. It's the only one that doesn't offer a helmet compatible hood.
This is an advantage because otherwise the hood is huge when you put it on. On top of that when the hood is down it just looks too big and funny.
"Our winters are very cold in my city. But I want to stay active throughout the winter. A lot of winter hikes, outdoor hockey, skiing, cycling, climbing and more; as well as everyday use. Lifespan and weather resistance of my new jacket is crucial for me."
Absolutely go for the Beta AR.
Performance data axis of synthetic jackets (table above) and shell jackets (this table) are different. Don't compare them.
Name Activity Temp (F/C) Breathability Weather Res. Durability Bottom line Review Pit zips? Two way zipper? Stuffs into itself? Face Fabric Fit Weight Length Alpha (aka AR) (Men's - Women's) Climbing N/A 8/10 9/10 8/10 4/10 Go-to climbing harshell. Review Yes No No N40d & N80d Most Rugged 3L Gore-Tex Pro Regular 430 g / 15.2 oz 79.5 cm / 31.25 in No Alpha FL (Men's - Women's) Climbing N/A 7/10 No data No data 10/10 No No Yes Hadron 3L Gore-Tex Trim 209 g / 7.4 oz 76.5 cm / 30 in Yes Alpha IS (Men's) Climbing 23/-5 7/10 5/10 No data 8/10 No Yes Yes N40p-X 2L Gore-Tex Regular 610 g / 1 lb 5.5 oz 78 cm / 30.75 in Yes Alpha SL (Men's - Women's) Climbing N/A 5/10 7/10 No data 9/10 No No Yes N40p 3L Gore-Tex Trim 326 g / 11.5 oz 77.5 cm / 30.5 in Yes Alpha SV (Men's - Women's) Climbing N/A 8/10 10/10 10/10 3/10 Strongest climbing hardshell. Review Yes No No N100d Most Rugged 3L Gore-Tex Pro Regular 510 g / 1 lb 2 oz 78 cm / 30.75 in No Andessa (Women's) Skiing 8/-13 10/10 No data No data 1/10 Yes No No N40d 3L Gore-Tex Trim 869 g / 1 lb 14.7 oz 67 cm / 26.4 in Yes Andessa Shell (Women's) Skiing N/A 5/10 No data No data 3/10 No No No N70p 3L Gore-Tex Trim 560 g / 1 lb 3.8 oz ? Yes Beta (Men's - Women's) All Round N/A 6/10 7/10 7/10 8/10 Streamlined all-doer shell. Review No No No N30p-X 3L Gore-Tex Trim 300 g / 10.6 oz 76 cm / 30 in No Beta AR (Men's - Women's) All Round N/A 8/10 9/10 9/10 4/10 Go-to all-round harshell. Review Yes No No N40d & N80d Most Rugged 3L Gore-Tex Pro Regular 460 g / 1 lb 76 cm / 30 in No Beta AR StormHood (Men's - Women's) All Round N/A 8/10 9/10 9/10 4/10 Review Yes No No N40d & N80d Most Rugged 3L Gore-Tex Pro Regular 460 g / 1 lb 76 cm / 30 in No Beta Coat (Women's) All Round N/A 6/10 5/10 No data 5/10 No Yes No 3L Gore-Tex Regular 320 g / 11.3 oz 88 cm / 34.5 in No Beta Down Insulated (Men's) All Round 0/-18 9/10 7/10 8/10 No data Yes Yes No 2L 40D Gore-Tex Regular 760 g / 1 lb 10.8 oz 79 cm / 31 in No Beta Insulated (Men's - Women's) All Round 21/-6 9/10 7/10 8/10 No data Go-to hybrid jacket. Review Yes Yes No N40d 2L Gore-Tex Regular 680 g / 1 lb 8 oz 78.5 cm / 31 in No Beta Insulated Coat (Women's) All Round 16/-9 7/10 No data No data No data No Yes No N40d 2L Gore-Tex Regular 600 g / 1 lb 5.2 oz 86 cm / 34 in No Beta Lightweight (Men's - Women's) All Round N/A 8/10 7/10 7/10 6/10 Review Yes No No N40p 3L Gore-Tex Fitted 380 g / 13.4 oz 75 cm / 29.5 in No Beta Long All Round N/A 4/10 9/10 No data 3/10 Review No No No N80p 3L Gore-Tex Regular 441 g / 15.6 oz 85 cm / 33.5 in Yes Beta LT (Men's - Women's) All Round N/A 7/10 7/10 8/10 6/10 Review Yes No No N40d 3L Gore-Tex Fitted 395 g / 13.9 oz 76 cm / 30 in No Beta LT Hadron All Round N/A 7/10 6/10 4/10 5/10 No No No Hadron 3L Gore-Tex Fitted 255 g / 9 oz 76 cm / 30 in Yes Beta SV (Men's - Women's) All Round N/A 8/10 10/10 10/10 3/10 Strongest all-round harshell. Review Yes No No N80p-X Most Rugged 3L Gore-Tex Pro Regular 495 g / 1 lb 1.5 oz 79 cm / 31 in Yes Cassiar (Men's) Skiing N/A 8/10 7/10 8/10 3/10 Review Yes No No N70p 3L Gore-Tex Trim 820 g / 1 lb 12.9 oz 74.5 cm / 29.3 in Yes Cassiar LT (Men's) Skiing N/A 6/10 6/10 6/10 5/10 Review Yes No No N70p 3L Gore-Tex Trim 605 g / 1 lb 5.3 oz 75 cm / 29.5 in Yes Cita (Women's) Running N/A 7/10 4/10 5/10 10/10 Review No No Yes Lumin Trim 120 g / 4.2 oz 67.5 cm / 26.5 in Yes Cita SL (Women's) Running N/A 7/10 4/10 4/10 10/10 Review Yes No Yes Permeair 20 Trim 65 g / 2.3 oz 61.5 cm / 24.2 in Yes Gamma (aka LT) (Men's - Women's) All Round N/A 7/10 3/10 7/10 3/10 Go-to softshell. Review No No No Wee Burly Double Weave Regular 545 g / 1 lb 3.2 oz 76 cm / 30 in No Gamma SL (aka lightweight) (Men's - Women's) All Round N/A 7/10 2/10 6/10 5/10 Review No No No Fortius 1.0 Trim 310 g / 10.9 oz 74 cm / 29.1 in Yes Gamma MX (Men's) All Round N/A 6/10 4/10 8/10 3/10 Strongest softshell. Review No No No Fortius 2.0 Regular 555 g / 1 lb 3.6 oz 74 cm / 29.1 in No Incendia (Women's) Skiing N/A 8/10 9/10 9/10 3/10 Review Yes No No NP100d 3L Gore-Tex Trim 610 g / 1 lb 5.5 oz 79 cm / 31 in Yes Incendo (Men's) Running N/A 7/10 4/10 5/10 10/10 Review No No Yes Lumin Trim 125 g / 4.4 oz ? Yes Incendo Airshell (Men's Running N/A No data No data No data No data No No Yes ? Trim 105 g / 3.7 oz ? Yes Incendo SL (Men's) Running N/A 7/10 4/10 4/10 10/10 Review No No Yes Permair 20 & Canim Trim 80 g / 2.8 oz 73 cm / 28.75 in Yes Indencia IS Skiing No data No data No data No data No data Yes No No N80p 2L Gore-Tex Regular ? 78 cm / 30.75 in Yes Macai (Men's) Skiing 5/-15 7/10 7/10 6/10 1/10 Review Yes No No N40p-X 3L Gore-Tex Regular 990 g / 2 lb 2.9 oz 75 cm / 29.5 in Yes Macai Lightweight (aka LT) (Men's) Skiing 8/-13 7/10 7/10 6/10 2/10 Review Yes No No N40p-X 3L Gore-Tex Regular 855 g / 1 lb 14.2 oz ? Yes Macai Shell (Men's) Skiing N/A No data No data No data No data Review Yes No No N80p-X 3L Gore-Tex Regular 775 g / 1 lb 11.3 oz ? Yes Micon (Men's) Skiing N/A No data No data No data No data Yes No No N80p 3L Gore-Tex Regular 685 g / 1 lb 8.2 oz 83 cm / 32.5 in Yes Micon Heather Skiing N/A No data No data No data No data Yes No No NP100-d 3L Gore-Tex Regular 685 g / 1 lb 8.2 oz 83 cm / 32.5 in Yes Nodin (Men's - Women's) Running N/A 8/10 5/10 5/10 10/10 No No Yes 20D Tyono Trim 130 g / 4.6 oz 75 cm / 29.5 in Yes Norvan LT (Men's - Women's) Running N/A 5/10 5/10 8/10 6/10 No No No N13p 3L Gore-Tex Trim 190 g / 6.7 oz ? Yes Norvan Shell (Men's Running N/A No data No data No data No data No No No 13D 3L Gore-Tex Trim 190 g / 6.7 oz 73 cm / 28.75 in No Norvan SL (Men's - Women's) Running N/A 7/10 6/10 8/10 8/10 Review No No Yes Gore-Tex Infinium Trim 120 g / 4.2 oz 77 cm / 30.4 in Yes Norvan SL Ins. (Women's) Running 39/4 No data No data No data No data No No Yes Gore-Tex ShakeDry Trim 270 g / 9.5 oz 71.5 cm / 28.1 in Yes Norvan Windshell (Men's Running N/A No data No data No data No data No No Yes Permeair 20 Trim 90 g / 3.2 oz 73 cm / 28.75 in Yes Procline (Men's) Skiing N/A No data No data No data No data Yes No No N70p Gore-Tex Infinium Trim 720 g / 1 lb 9.4 oz 76 cm / 30 in Yes Ravenna (Women's) Skiing N/A 8/10 7/10 8/10 3/10 Review Yes No No N70s-4 3L Gore-Tex Trim 725 g / 1 lb 9.6 oz 69.5 cm / 27.4 in Yes Ravenna LT (Women's) Skiing N/A 6/10 6/10 6/10 5/10 Review Yes No No N70p 3L Gore-Tex Trim 540 g / 1 lb 3 oz 69 cm / 27.2 in Yes Rush (Women's) Skiing N/A 8/10 9/10 9/10 3/10 Go-to ski jacket. Review Yes No No N80p-X & N100p-X 3L Most Rugged Gore-Tex Pro Regular 590 g / 1 lb 4.8 oz 79.5 cm / 31.25 in No Rush (Women's) Skiing 16/-9 3/10 5/10 5/10 9/10 Review No No Yes Hadron 2L Gore-Tex Infinium Regular 515 g / 1 lb 2.2 oz 79 cm / 31 in No Sabre (Men's) Skiing N/A 8/10 8/10 7/10 2/10 Review Yes No No N80p-X 3L Gore-Tex Regular 705 g / 1 lb 8.9 oz 79 cm / 31 in No Sabre AR (Men's) Skiing N/A 7/10 8/10 7/10 7/10 Review Yes No No N70p 3L Gore-Tex Regular 700 g / 1 lb 8.7 oz 79 cm / 31 in Yes Sabre Insulated (See related products) Skiing No data 7/10 No data 6/10 No data Review Yes No No N80p 2L Gore-Tex Regular 815 g / 1 lb 12.7 oz 76 cm / 30 in Yes Sabre LT (Men's) Skiing N/A 7/10 8/10 7/10 8/10 Review Yes No No N80p 3L Gore-Tex Regular 660 g / 1 lb 7.3 oz 83 cm / 32.5 in Yes Sabre SV (Men's) Skiing N/A 10/10 10/10 10/10 1/10 Strongest ski jacket. Review Yes Yes No N100d Most Rugged 3L Gore-Tex Pro Regular 595 g / 1 lb 5 oz 85 cm / 33.5 in Yes Sentinel (Women's) Skiing N/A 8/10 7/10 7/10 2/10 Go-to ski jacket. Review Yes No No N70p 3L Gore-Tex Regular 640 g / 1 lb 6.6 oz 73.7 cm / 29 in No Sentinel AR (Women's) Skiing N/A 7/10 8/10 7/10 7/10 Review Yes No No N70p 3L Gore-Tex Regular 590 g / 1 lb 4.8 oz 72.5 cm / 28.5 in Yes Sentinel Insulated (Women's) Skiing 21/-6 8/10 No data No data No data Review Yes No No N80p 2L Gore-Tex Regular 600 g / 1 lb 5.2 oz 79.8 cm / 31.5 in No Sentinel LT (Women's) Skiing N/A 7/10 8/10 7/10 8/10 Review Yes No No N80p 3L Gore-Tex Regular 565 g / 1 lb 3.9 oz 73.5 cm / 29 in Yes Sentinel Relaxed (Women's) Skiing N/A No data No data No data No data Yes No No N80p 3L Gore-Tex Regular 655 g / 1 lb 7.1 oz ? No Shashka Stretch (Women's) Skiing N/A No data No data No data No data Yes No No N70p Gore-Tex Infinium Trim 670 g / 1 lb 7.6 oz 71 cm / 28 in Yes Sidewinder (Women's) Skiing N/A 8/10 8/10 7/10 2/10 Yes No No N80p 3L Gore-Tex Regular 570 g / 1 lb 4.1 oz ? No Solano (Men's - Women's) Around Town N/A No data No data No data No data Review No No No Gore-Tex Infinium Relaxed 355 g / 12.5 oz 72 cm / 28.3 in No Squamish (Men's - Women's) Running N/A 5/10 4/10 7/10 9/10 Go-to running jacket. Review No No Yes 30D Tyono Trim 140 g / 4.9 oz 77.5 cm / 30.5 in No Theriss Down (Women's) Skiing No data 7/10 6/10 7/10 2/10 Review Yes No No N80p 2L Gore-Tex Regular 709 g / 1 lb 9 oz 63 cm / 24.8 in No Trino SL (Men's) Running N/A 8/10 5/10 7/10 6/10 Review No No No Gore-Tex Infinium Trim 340 g / 12 oz 74 cm / 29.1 in Yes Trino SL Anorak (Women's) Running N/A 8/10 7/10 8/10 7/10 Review No No No Gore-Tex Infinium Trim 290 g / 10.2 oz 65 cm / 25.5 in Yes Venda Anorak (Women's) Around Town N/A No data No data No data No data No No No Gore-Tex Relaxed 255 g / 9 oz 75.5 cm / 29.7 in Yes Zeta AR (Men's) Hiking N/A 7/10 8/10 7/10 4/10 Yes No No 3L Gore-Tex Regular 425 g / 15 oz 80 cm / 31.5 in Yes Zeta FL (Men's - Women's) Hiking N/A 4/10 6/10 4/10 6/10 No No No N20r 2L Gore-Tex Trim 221 g / 7.8 oz 76 cm / 30 in Yes Zeta LT (Men's - Women's) Hiking N/A 5/10 7/10 8/10 5/10 No No No N40P-X 3L Gore-Tex Trim 335 g / 11.8 oz 78 cm / 30.75 in Yes Zeta SL (Men's - Women's) Hiking N/A 3/10 5/10 4/10 5/10 Review No No No 2L Gore-Tex Trim 310 g / 10.9 oz 77.8 cm / 30.6 in Yes
"More than half the time I'll be climbing with my new jacket."
Go for the Alpha or Alpha SV, depending on your own outer fabric needs and desires.
Alpha's are cut short in the front and longer in the back compared to Beta's. This not only allows for better leg mobility but also for better weather resistance when the climbing harness is on.
Also the higher chest pockets are more central around your body and hence don't mess with your center of gravity. They don't get blocked off when wearing the jacket with a climbing harness either.
Lastly the longer collar configuration covers your entire chin when you're looking up, although it might also chafe into your jaw and feel annoying in return.
Arc'teryx Alpha vs Beta: Gore-Tex membranes
Alpha SV is absolutely the most stiff, followed by Alpha (aka AR) and Beta AR. Beta Lightweight and Beta LT come up next and lastly the Beta.
All come with DWR.
DWR is a coating. It's basically sprayed on to the surface of these jackets as a finish. It stands for Durable Water Repellent - which means that water will be repelled under wet conditions instead of soaking into the fabric. DWR also decreases dry time. It's a good thing these jackets are coated in DWR. But pay attention to the fact that DWR is a coating - meaning that it will wear off over time. Which is why you might want to invest in a DWR spray such as this one at arcteryx.com for after treatment. As you see, there's a strong correlation between FP x FW and temperature ratings, but not more than, say, 80%. I explained why this happens here in this post of mine.
Together with the new arrival ski beast Sabre SV (Men's) and discontinued Incendia (Women's), the outer fabric of Alpha SV (100 denier) is the thickest Arc'teryx ever manufactured. It resists abrasion, wind and water so well that it's insane. Expect 20+ years of use.
Not only the thickness is 100d. It's 100d everywhere. This is another thing that makes the Alpha SV stand out.
Because most other jackets like Beta AR and Alpha (aka AR) are equipped with lighter and weaker face fabrics where resistance isn't needed as much.
You do get weight, breathability and cost savings in return with this strategy however. This obviously doesn't happen with the Alpha SV.
- Alpha line offers chest pockets that allows for crossover access even when the harness is on, Beta line offers hand warmers,
- Alpha line offers slightly longer in the back and shorter in the front (better for leg mobility & weather protection when the harness is on).
Going from these 3L Gore-Tex Pro models to base 3L Gore-Tex models (Beta, Beta Lightweight and Beta LT), let's take a look at what kind of difference the Gore-Tex Pro makes and in the end plays out in practice.

Beta Lightweight in Void.
So all 3L Gore-Tex membrane contain following layers, regardless of Gore-Tex Pro or not:
- Outer Layer: This is typically a durable fabric that is designed to withstand the environment and provide protection against wear and tear. It is often treated with a durable water repellent (DWR) to ensure water beads up and rolls off the surface.
- Middle Layer: This is the actual Gore-Tex membrane, which is what makes the fabric waterproof and breathable. The membrane contains over 9 billion pores per square inch; these pores are too small for water droplets to pass through but large enough to allow water vapor (sweat) to escape (< 0.02 µm in diameter).
- Inner Layer: Usually a backer material that is designed to protect the membrane and provide comfort against the skin. It can also help wick moisture away from the body.
0.02 µm in diameter is a very fine line. The size difference between molecules are microscopic. The difficulty in achieving such membrane is pretty much what makes Gore-Tex special and expensive.
As you can imagine, the subject pores vary in size. Getting each and every one of the pores the same diameter would skyrocket the manufacturing costs. So the efficacy here isn't 100%, not even close to it.
Compared to Gore-Tex, Gore-Tex Pro offers a better "hit rate", by achieving more accurately sized pores. This doesn't only make the Gore-Tex Pro more waterproof without compromising breathability. It also ensures a longer life at the same time. Because just like anything else these pores are prone to wear, tear and aging too.
The difference doesn't just lie in consistency of pore size, though. The inner Gore Micro Grid Backer technology and the outer rugged face are all causes of superior quality of Gore-Tex Pro. Read more about it here: https://www.gore-tex.com/pressroom/press-release/original-gore-tex-products/the-new-gore-tex-pro-membrane-technology.
Also check out: https://www.porellemembranes.com/our-technologies

As you see, you can't tell the differences between c-knit of Beta Lightweight (left) and tricot of Beta LT (right) just by looking at the photos. Yes it's the Beta Lightweight that comes with the LT tag on top of the internal zippered pocket.
Now let's get to the differences between Beta, Beta Lightweight and Beta LT.
The Beta does come with 30d thickness whereas the other two with 40d.
But I don't think that's equally as important as the differences in backer (i.e the inner layer mentioned above).
Beta LT comes with tricot technology, whereas the other two are C-Knit. This difference isn't visual.
- Tricot is woven nylon. It's the classic and most common backer used in non-Pro Gore-Tex jackets. It's more durable than the C-Knit but not that smooth to skin.
- The C-Knit, on the other hand, is made of a circular knit pattern, hence the prefix "C". It's lighter, more comfortable (stretchy) and less noisy. But also less durable. It also wicks.
Some people argue that Gore-Tex patches cannot be used with C-Knit backers. But I don't get it. I never needed to use one before, but I see no reason why it wouldn't work.
Lastly, the remaining three insulated models ("Beta Insulated" line) come with 2L Gore-Tex. The missing layer is the inner layer.
Arc'teryx Alpha vs Beta: Breathability
Keep in mind that breathability differences that occur because of membrane differences mostly aren't that noticeable in practice. The thing that matter the most is the mechanical venting, i.e pit zips.
Beta is the only one that doesn't offer pit zips. If you rarely get hardshells then I'd strongly recommend you to think twice before getting one without them.
Arc'teryx Alpha vs Beta: Hoods
Beta AR is the only one that's offered in DropHood optionally.
I surveyed 100+ visitors and roughly 60% of them voted for StormHood over DropHood. I'm camp DropHood but maybe that's because I own many StormHood items so I like the variety here. Read more about StormHood vs DropHood here.

StormHood of Alpha (aka AR) at left and DropHood of Beta AR at right.
But generally speaking, DropHood is separate from collar and draws up around it. In StormHood there's no separate collar. The former feels more comfy when the hood is down and the latter more so when it's up.
Arc'teryx Alpha vs Beta: Cuffs
Left to right: Beta, Beta Lightweight, Beta LT, Beta AR, Alpha (aka AR) and Alpha SV.

Arc'teryx Alpha vs Beta: Pockets
Beta LT doesn't offer an internal zippered security pocket.
In addition to the two external pockets that any shell typically offers, and all the shells in this review do offer, the Alpha SV features an external sleeve pocket and a giant internal dump pocket (measuring 8.7 inches (or 22 cm) by 7.1 inches (or 18 cm)).

Dump pocket of Alpha SV.
Arc'teryx Alpha vs Beta: More photos

Beta.

Beta Lightweight.

Beta LT.

Beta AR.

Alpha (aka AR).

Alpha SV.