Been wearing these all winter here in the Pacific NW- keep my feet warm and dry, although my feet do tend to sweat a bit after several hours.  Do get 1 size larger than a regular Croc, though. Wish Croc would make a replacement liner for these- plus the liner is very difficult to get out to clean, but that is the only gripe I have with them.  I've got two pair and they are great and look good too!