Wonderful jacket. Looks very cool. Got it in black to wear around town but I could definitely use it on the mountain also. This technology does breathe while maintaining it waterproofing ability. This is especially nice when going inside for a minute. I'm always hot anyways so I really can't stand jackets that don't breathe. The sizing is "normal," not too big, not too small. I'm 5'10" 235lbs and the XXL is fine for me. I pretty much wear XXL in everything. Bottom line is that with Patagonia, you know you're getting quality. Arms are just a tad long but I just tighten the button on the end of the sleeves and problem solved. It has down but I don't walk around looking like pillsbury doughboy because of too much down. I see myself using this for many years to come. Thanks backcountry....