Kuiu is a superior product to Sitka, and it cost less as well. The main drawback is not having it available in every retail outlet and periodic back order delays. This is a direct result of the lower price. If you want it all available on the shelf everywhere you go, you have to pay the higher retail prices.
I am happy with planning ahead and saving about 30-40% over Sitka, and getting a better product. I leave my Sitka home now and wear Kuiu. The Kuiu Guide jacket is lighter in weight than the Sitka jacket, and just as warm.
In the constant rain of SE Alasak, the Healy Hansen Impertec is a great lightweight rain gear. The Kuiu rain gear is great, but anything that breathes will never be as waterproof as a solid "rubberized" fabric. Ditto for Sitka rain gear. You can either be damp inside from the "plastic" rain gear, or eventually a bit damp from wearing a breathable fabric. Either way, after multiple days in constant rain you will at least be a bit damp on the inside... Change clothes often, and dry clothes out by a fire (in a cabin, preferably) and you will be fine, but it is very hard to stay dry indefinitely in constant rain anywhere.
llp