I've got Gray Wolf, Filson, Woolrich and an Asbell pullover. All are nice for their intended uses. But for good, long lasting wool you can't beat Filson. It costs more, but worth it in my opinion. That being said, my Gray Wolf is great stuff too and Jeff is a super guy to deal with.
What are you looking to buy (shirt, jacket, vest, pants, etc)? My most versatile and favorite piece of hunting clothing is my Filson wool vest. Most likely I'll be buried with it on, unless a future grandson takes a shine to it. Lol!