This jacket has become my favourite this winter! I have technical jackets that I use for more strenuous activities, but this works a a GREAT insulator for minimal to moderate activity. It is definitely windproof, but I have not tested it in temperatures below 10 F. I have worn it sitting around campsite and light night hikes, and it has exceeded my expectations. I always had a problem with sitting still and being cold, but this solved it as easy as the Pythagorean theorem! Also, Patagonia is an ethical company that invests in is future (i.e., workers and the environment), so I like supporting them. Cheers!