I have these in black and loved them so much I got them in dark brown too.  The dark brown is called "dark red" for some reason, but they are a deep chocolate brown.) The black ones rubbed just a little on my heel the first day, but after that they were perfect.  The brown ones never rubbed at all.  I can wear these all day and they feel great.  I'm a size 8.5, and that size fit perfectly.  Really cute with skinny jeans. May buy a 3rd color!