I just used mine for 6 days above tree-line. It was impressive when pair with ambient. I had wind gusts up to 40-50mph, rain and hail. Wind block and moisture management qualities exceeded expectations. You dont realize how well that back panel breaths until its 20 degrees with wind chill and wind is coming from behind you.
After trying one on, one thing to cover (which I am sure you will) is fit. I see you've posted you normally a L for Sitka but had to size up in the Evo to permit over mid-layer wear. I'm doing the same - I'm a medium in everything, and it only fit over a baselayer in that size in the store. As much as Sitka pushes this piece as perfect for use with their ambient midlayers, I'm surprised the "standard" fit of it (per their website) is cut so close.
Either way, good to hear it is versitile. That's what shines about that ambient hoody, you can really push hard in it without taking it off. Having a windshirt that's flexible like that (albiet at a bit of a weight penalty compared to most) sounds incredibly useful.