I have enjoyed the WB clone I built from 1.1 ripstop. Below 15 F I get a little frost inside. Warmer that 15 F, the top of the sock becomes moist without freezing. If I built a new sock, it will be to use a sub1 oz fabric. My sock is about 8 oz, but an investment of $90 would buy the material for a 4 oz momentum 50 Sock.
The sock keeps me very warm, much better then without especially of there is wind.