I know this thread is about the Vista but my comments apply to the Quito too, which I own.
Anecdotal evidence. Today, its wet in NorCal bay area and the weather about 60F at sealevel. The forecast was for dry afternoon, 10% chance of rain, and with heavy rain forecast tomorrow, I took the "window" opportunity to bike into the hills on what turned out to be 4 hours of continual rain. Aside - so much for weather forecasts.
On the ascent up to 2600ft, there is nothing neither windproof not waterproof which lets warm air escape well enough so in rain I simply let myself get wet, my heat output high enough I was steaming in just a baselayer. Rain being just cleaner alternative to sweat.
At the peak, I took off my base, squeezed all the water out of it, put it back on, and I donned a Paramo Quito. The chilling effect of the descent, approx 2000ft in 10mins, meant I was needing a fair degree of insulation both during descent and then about 20mins after as I got back up to warm again. The Quito kept me warm enough, the significant reasons being the Velcro sleeves (not elasticated, so tight), the cinch cords around the waist, the hood with cinch cords at front and rear.
Once I felt warm enough again at the bottom of the hill, I then removed the Quito to check the baselayer, it was dry. The breathability of the Paramo design and my body heat had dried out a rain-sodden baselayer in about 30mins.
I kept on the Quito but vented it a lot, all the zips open, sleeves up for a generally lower-output return home, in the rain.
At home, I removed the Quito, shook it then put it back on and in about 30mins it dried fully from body heat then removed to use another day. I accept if I were to enter a tent all that damp would be dumped into condensation.
The downside of Paramo is the too-much-insulation problem, but once you learn it has immense breathability which only needs body heat, that insulation becomes part of the system which leads to comfort.
With a shell, you have to avoid overheating, the shell fabric cannot breathe enough if you're overheating, but with Paramo a different set of issues, you can delay putting it on til you are about to be chilled, over wet clothing, and then let yourself get too warm, that heat then dries yourself skin-out. Paramo also creates the problem - you have to delay putting it on due to its too-warm insulation problem. Just a different approach to using a shell.
Generally, Paramo is too warm for my home area. I wear it far far less than when I was in UK, but it still has a useful role. If I did not own Paramo I'd have done things differently, probably added a windproof earlier in the ascent to reduce soaking of my baselayer, then added an insulating layer like a thin Primaloft layer and then removed that insulation later. I'd have carried similar insulation to the Quito but not have been as comfortable.