i love patagonia, business model, environmental action, photos, etc. so it is hard for me to be unbiased. the Icebreaker gear i have is just so damn good. this is my favorite piece of gear from them. the 260 longjohns are awesome too! a buddy of mine has a pro deal with smartwool and although i prefer their socks, icebreaker makes far superior products.
good luck finding something better than this for midweight. i always wear this snowboarding, often take it with me on high elevation mtn bike rides. i never take a field trip (northern NM) without it.