The part of the shoe that sits against the back of the heel is NOT soft.  When I first tried these on, they rubbed my heel red.  The good news is that you can unzip the back zipper which helps tremendously.  The bad news is that you can't unzip the zipper without it being VERY noticable unless you're wearing jeans that cover it.

Still, [the one I ordered was] a cheaply priced shoe ($19.98).  Given the price, I thought was a pretty good deal when weighed against the cost.