I also wear a light layer of wool over the UnderArmor if its really cold with another waterproof layer over it..
IMHO, the best way to address cold weather issue is too dress in layers..
Have a wicking layer closest to your skin..so if you are hiking,etc..it will pull the moisture off of your skin..then an underarmor layer or similar. ..then wool and finally a water proof layer..i use Cabela's MT-50 jacket and pants..
If it gets really cold---minus 10 to minus 30F...I put on heavier wool garments but still put a water proof outside layer on..enables me to sit on the snow or terrain without getting wet and if its snowing or blowing..still keeps the wet off me...
Have been using this system for a long long time..works very well for me.
thanks
Ripp
-------------------- ALL MEN DIE, BUT FEW MEN TRULY LIVE..