Christopher S wrote a review of Patagonia Capilene 4 Expedition Weight Bottom - Men's on January 1, 2013
Familiarity: I've used it once or twice and have initial impressions
I have a pair of the old, very thick expedition weight underwear. Despite Patagonia's description, these really are mid-weight. My first time out in them I was definitely cooler, and not in a good way. While the open-grid construction adds breathability, I've gone back to my old pair for colder days, or times when you are standing around more (ice-climbing belay, e.g.). A bit of a disappointment, and I'm a big fan of Patagonia clothing.