First Lite and Kuiu is pretty much all I use. I hunt white tail in Louisiana and 3rd rifle Elk in Colorado every year. For base/mid layer, I am all about First Lite merino. It's warm, yet breathable, it somehow makes you not stink when you've gone days without a shower, and still keeps you warm if you take a tumble into a creek. and it's so soft and comfortable. I've tried Kuiu base layers and they just weren't as comfortable as the First Lite, I think they were not nearly as good wicking sweat/moisture away.
I've got a set of the Kuiu Super down puffy jacket and pants and they are fantastically warm and decently rugged considering how light and packable they are. Also have a few different Kuiu pants, hat, gloves, etc and they are great as well.
For me, I just buy whatever is on sale between the two... except for the base/mid layers, I won't settle for anything except First Lite Merino stuff! (i have an old Chama Hoody that I wear on a weekly basis for the last 10 years and it's still going strong)