I agree with Rob. Was fortunate enough to have a buddy upgrading and purchased his older set of Fanatic bibs and jacket. I was treestand hunting in the lower teens with light snow. Had nothing other than the bibs and jacket and my underwear and was completely warm. Very happy. The only downside is its only that cold here a couple times during the deer season.
Now I am looking into getting a few other pieces for early season. Probably go with a First lite merino base layer and then finish it off with a few Sitka pieces. Looking at the Mountain pants, Core light weight hoodie, Apex hoodie and then the Kelvin active jacket.
Rob do you have any experience with those?