Not much to say that hasn't been said before, I have several of these and use them for mountain biking, rock climbing, mountaineering, running, camping, working outdoors over winter - generally anytime I am likely to build up a sweat! The wicking action is very effective, keeping you dry, and they are incredibly fast drying, light weight and pack away in the smallest of places so great for camping, trekking etc
Thoroughly recommended - only advice is do not dry in a tumble dryer (my wife did and they shrink/shrivle/melt!)