So comfortable....the footbed is like an athletic shoe.....I could walk all day in these.  I love that they have no zippers.  Zippers can get clogged with dirt, and let in cold and rain.  These will work well for the winter; they make my ankles feel toasty.  I wear a size 8 Medium and size 9 in athletic shoe.  I ordered a size 8 and they fit well; lots of room for the toes.  Width is quite wide.  I do not recommend these for someone with a very narrow foot.  These are now my "go-to" boot.....easy to pull on and could be worn with no socks.  However, there is no fleece covering in the shoe for your foot bottom......so if you are looking to walk on fleece, these would not be the boot for you.  I like the feel of these better than any of the other fleece boots that I have tried.  The thick sole of the shoe provides more insulation from the ground.  Nice mid-calf height....and can be rolled down.  These FitFlop boots will make you want to throw out all your other winter boots.