I have never worn or owned Sitka so I can't speak to durability. I can say though I've never had durability issues with my Kuiu gear, including overall craftsmanship (such as seams coming loose or something). Additionally Kuiu has a lifetime warranty on their products (not sure what Sitka offers).
Also, if I may slightly contradict my previous comment about Kuiu not keeping you warm while stationary...
...right now I'm in a ladder stand. It's 41°F with a "feels like" 36° from the wind. I've been here for 2 hours so far and I am perfectly comfortable (other than my toes and fingers, which is unrelated to Kuiu gear). My layers are:
Head: Walmart beanie and Kuiu balaclava
Upper: Kuiu Peloton 118 longsleeve, Cold Pruf baselayer (Amazon), Kuiu Kenai Ultra (for insulation), Peloton 240 hoodie (to block wind)
Lower: non-kuiu stuff
I dont have lower body Kuiu stuff because I can't make up my mind on what I want. If I need anything warmer I have some insulated/waterproof/windproof layers from
BassPro I can throw on.
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