These are some seriously stout socks. They are thicker than I expected and are a bit of a struggle to put on and take off due to their somewhat rigid structure. However, they are extremely comfortable and very warm.
So far I've worn them in temperatures between 45 and 70 degrees in well ventilated shoes (Adidas Trailcross) and the socks have exceeded expectations. I thought they might be too warm for the mild Florida winters, but even at 70 degrees my feet did not overheat. I don't plan on putting them to the waterproof test, as our rainy season is in the summer.
It's not as warm as the marketing hype would lead you to believe. The water/windproofness of the sock is the strongest point IMO. It's not any warmer than the heavier wool cycling socks I have. Overall, it is a very usable cold weather cycling sock.
Sock is a bit stiffer than comparable products from other brands but these socks do a great job of keeping your feet warm as long as you have enough extra room in your shoes. I wear them with a pair of Sidi Gore lined winter shoes and they work great. The issue is really around their flexibility and comfort, they feel stiff when you first put them on, but in a cycling shoe that is not a big deal. Great fishing socks as well.
Not a good cycling sock it's too thick !
