i saw that no one replied and being your first post WELCOME! I wanted to comment on my experience with the expedition weight polypropolene. i think it works great but i love wool better. the polypropolene tends to get stinky and when you wear it next to your skin and you sweat a bit it feels like thousands of tiny cold water drops. kinda a gross feeling. polypropolene sock liners next to your skin leaves my feet feeling clamy. my feelings is that although in the laboratory polypropolene may wick water away i think its better to wear poly over a light layer of wool. wool i believe can hold more moisture before loosing its warmth properties. you also need loft and trapped air space so i like to get loose fitting cloths over my intial next tothe skin layer. if all else fails just get one of these http://www.warmers.com/ItemDetails.a...oryID%7citemid