I've gone back and forth on it. It is expensive, but it does come in warm light weight packages. I've gone to all sitka gear for western hunts (spot and stalk in chilly temps/ anything in the mountains with lots of walking involved), but for treestand hunting I haven't made the leap.
I've had the incinerator bibs and jacket on my wish list for treestand hunting, but thats going to be a tough pill to swallow.