I bought these as part of a deal, and didn't have to pay too much for them.  I was so excited to get them... Thought the sturdy rubber sole would be excellent for having to take my dogs outside, and the warm inside was perfect for cold nights and cold feet!  HOWEVER... I found the upper part of the heel that rests against the back of your ankle was extremely rigid and uncomfortable!  I had hoped it would stretch out or soften after repeated use, however it never seemed to at all.  Even attempted to stretch it via shoe shaper... still, no good!