Excellent - Caused me to Buy 5 other Icebreaker Products!
I have used this top twice while backpacking. The first time was a day hike in about 60-65F weather. The breeze cut thorugh it and kept me just the right temp. When I stopped my back was a little wet from the backpack and sweating, but I was very comfortable while lounging and enjoying the scenery. The second trip it was 40-50F. This time I had a full 50 lb pack for a quick overnighter. While hiking it was perfect. The zip allowed me to control my temp and I never overheated, but felt comfortable. When making camp I was fine and when the wind kicked up added a MH Power Stretch and hat. I couldn't believe I was still warm. I needed nothing else. I am 6', 170#, 33 in waist, and the large is perfect. I have worn it in public on the way to hiking and was at first a little self conscious, but as I get older I don't give a rat's A$$ anymore. My wife says it just shows that I am fit and will even be seen with me, so it must be fine. I also bought a 260 and assorted leggings based on my great experience with the 200. It hasn't been cold enough to wear them out, although I did wear the lightweight leggings for PJs and I was very warm. I'm sold on icebreaker.