I would agree. Pile is fine as long and your are not going to be anywhere near a open flame. Unfortunately that presents quite a problem if you need to start a fire. All the pile pullovers I own and have taken camping/hiking have at least a half-dozen burn holes where sparks hit me (most of the time without me noticing). IMHO nothing beats wool socks, period. Any benefits of pile over wool are not worth the risk with regard to tops and bottoms. That being said the idea of wool underware does not particularly appeal to me, so maybe I am a hypocrite.