I'm using this in all my high output activities from skiing to snow shoveling. It replaces my fleece because of the breathability. It's also wind/rain resistant, so I don't have to put a shell over this one as I do with a fleece.
Kind of a miracle insulation. For wetter weather, I put my waterproof shell over this. I've gotten really hot and sweaty, but I didn't get wet from my sweat!
This review was written in the old system and had content requirements that are different than reviews written today.