These boots might well have kept my feet warm as advertised and I would have been grateful for it. Sadly, I couldn't find a size that fit well on my size 13-14 feet. No matter the size, you are likely to find these boots to be heavier than any other boot you've worn. My cold feet are caused by spine damage, so extra heavy boots weren't going to be safe for me, no matter the size. But, if I were going to be out in the cold, not needing to tromp around, these would have probably made for happy feet.