So I was wondering about this and couldn't really find any info online. So I ended up contacting Patagonia's Customer Service (see full chat text below).
In summary; if you want to maximize warmth and weather protection; then Tres is probably your best bet - since it's very, very warm (equipped with a whooping 150 grams of down). Otherwise, I'd recommend you to base your decision on their looks above all else.
Speaking of which - Tres look prettier to most (especially this Deep Plum Color is really liked by many (patagonia.com) - including me).
I'd say, generally speaking, when it's dry out, with only a long sleeved shirt under and without a shell on top, with a mild wind and a very low to no activity level...
The approximate lowest temperatures an average person can wear these jackets without feeling cold can be listed as around -5 deg F (-20 deg C) for Tres and around 10 deg F (-12 deg C) for Vosque.
If you think you run hotter or colder than the average person, then shift these temperatures ranges accordingly.
Here's my chat with the awesome Patagonia Rep Alex
Alex (08.01.2020 17:09:54): Hello Canberk! My name is Alex. How may I help you today?
Canberk (08.01.2020 17:10:46): Hi Alex!
Alex (08.01.2020 17:10:51): Hey there!
Canberk (08.01.2020 17:10:53): I'm gathering information for a wide range of possible buyers of Women's Vosque and Tres Parkas (all for possibly different types of purposes), so I'd appreciate if you could share their technical & practical differences with me, as well as their most suitable intended uses. What are the advantages & disadvantages of one over the other?
Alex (08.01.2020 17:11:13): Sure, let me pull them up.
Canberk (08.01.2020 17:11:17): How do they compare in terms of warmth, breathability, durability, weather resistance and bagginess/fit?
Canberk (08.01.2020 17:11:19): Thank you!
Alex (08.01.2020 17:11:23): Of course!
Alex (08.01.2020 17:12:54): So the Tres Parka will be warmer and will weigh a little more. The outer shell on the Vosque is a little more durable, but not by much.
Alex (08.01.2020 17:13:03): Both are waterproof.
Canberk (08.01.2020 17:13:32): Alright
Alex (08.01.2020 17:13:38): The Tres Parka uses Down Insulation while the Vosque uses Synthetic Insulation too.
Alex (08.01.2020 17:14:05): Down won't stay warm if it soaks through if you're wearing just the inner layer on its own, synthetic will.
Alex (08.01.2020 17:14:51): But both inner layers are water resistant - so they'll repel light rain/snow for around an hour or two, or heavy rain/snow for about 5-10 minutes.
Alex (08.01.2020 17:15:20): That's basically all the major differences there!
Alex (08.01.2020 17:16:03): Did you have any other questions about these at all?
Alex (08.01.2020 17:16:23): Or about anything else?
Canberk (08.01.2020 17:16:46): Thank you so much Alex!
Canberk (08.01.2020 17:16:52): These are very, very helpful
Canberk (08.01.2020 17:16:56): How warmer is the Tres than the Vosque?
Alex (08.01.2020 17:16:58): You got it!
Alex (08.01.2020 17:17:16): It's noticeably warmer. Where do you live?
Alex (08.01.2020 17:17:21): Or where will these be used?
Canberk (08.01.2020 17:18:15): Ah I'm not looking to get them just for myself or a specific type of user
Canberk (08.01.2020 17:18:26): It's more for a wider range of buyers
Alex (08.01.2020 17:18:28): The Vosque will be more versatile then.
Alex (08.01.2020 17:18:32): Since it's less warm.
Alex (08.01.2020 17:19:03): You'll have a greater temperature range that you can wear it in, and if someone is in a colder part of the world, they can layer a light fleece under it in the winter.
Alex (08.01.2020 17:19:19): Then it'll be a Spring/Winter/Fall coat.
Canberk (08.01.2020 17:19:37): How many grams of down does the Tres have?
Alex (08.01.2020 17:19:39): The Tres is more ideal for just winter, it's a bit warm for Spring and Fall in a lot of places.
Alex (08.01.2020 17:19:41): Let me see.
Canberk (08.01.2020 17:19:48): Thank you!
Alex (08.01.2020 17:19:52): Sure thing!
Alex (08.01.2020 17:20:35): 150 grams
Canberk (08.01.2020 17:20:56): And it isn't equipped with any synthetic insulation, right?
Alex (08.01.2020 17:21:02): Not on the Tres, no.
Canberk (08.01.2020 17:21:23): What about the amount of down in Vosque?
Alex (08.01.2020 17:21:35): It doesn't have Down, it uses synthetic insulation.
Alex (08.01.2020 17:21:38): Let me see how much.
Canberk (08.01.2020 17:21:56): OK, I'm waiting, thank you!
Alex (08.01.2020 17:22:30): You got it!
Alex (08.01.2020 17:24:38): So synthetic insulation isn't measured by overall weight, it's measured by how much a 1 meter by 1 meter piece of the insulation weighs. In the Vosque, it uses 100 grams of synthetic insulation.
Canberk (08.01.2020 17:25:03): I see
Canberk (08.01.2020 17:25:11): I guess that's it, then
Canberk (08.01.2020 17:25:16): Thanks a lot Alex!
Canberk (08.01.2020 17:25:19): Have a great day
Alex (08.01.2020 17:25:22): You got it Canberk!
Alex (08.01.2020 17:25:32): You too! Let us know if you have any more questions come up!
Alex (08.01.2020 17:25:38): Thanks for chatting in! If you have a moment, I'd really appreciate it if you would take this quick survey: [link]