I took the plunge and bought the Sitka downpour jacket and pants this year. I really had a hard time dropping that much coin on "rain gear", but after another uncomfortable and disappointing hunt in my old stuff this early season, I had had enough! I did some research, and it came down to Sika or Kuiu. Kuiu didn't have my size in stock, and I found a discount on the Sitka, so that's what I bought. I think the Kuiu might perform a tad better, but I will say that I am very happy with the Sitka gear. The fit is absolutely perfect for me, and is very comfortable. It has performed extremely well both on stand, and traveling to/from my stand. I never sat in a downpour, but the light to moderate precipitation that I did hunt in, the gear kept me dry both from the elements and from sweat. I wear First Lite merino wool underneath, and I'm sure that helped.
Actually, the First Lite stuff is new this year as well. I have enjoyed my hunts, and been more comfortable than ever this year.
I found myself wearing the Sitka gear much more than I anticipated, because it fit so well, and is a great layer to cut the wind from blowing through your wool. I wish I would have invested in this stuff years ago!
The one downside to the downpour series is noise. While not excessively loud, compared to wool its a bit noisy. And it does scratch against rough tree bark. And when the temp drops below probly 40*F, the fabric stiffens up a bit and makes noise when you move. But an Asbel wool jacket or the like, over the top of it, and problem solved.
Over all, I am very pleased with these garments. When it's warm, noise is not an issue (except for tree bark), when it's cold noise becomes an issue, but you'll want another layer or two anyway, and a wool layer over the top is the perfect solution.