Your service has been excellent. I won't really know how warm the socks keep my feet until it gets cold. I have noticed that even the pairs of socks that are the same size don't feel the same on my feet. The latest size 11 doesn't seem as large as the first size 11 I bought, but the first size 11 shrunk a little when I washed them. So they feel great now. One thing I noticed are the knots by the toes. In some socks I don't feel them at all; some socks I have worn inside out so they don't rub. One pair out of my four are very uncomfortable because of the knots. My shrunken size 11 and one of my size 9 that was not washed feel the best on my feet. I'm afraid to wash the again!