I bought these in anticipation for a trip to Chicago where I knew that I was going to be doing a lot of walking downtown and through museums, etc. I remember one reviewer complained that the hole was very small to fit your foot through. It was a little snug, but once my foot was in, it was fine.  The first day I wore them I thought they were the most comfortable shoes ever!  I really enjoyed how light they were and how they supported my feet.  The second day, we walked four miles and I ended up with raw, bloody blisters on my heels.  I'm not sure why the difference in the two days, I really didn't wear different types of socks, but my feet were a painful mess.  It's been a couple of weeks and I've just started wearing them again.  This time I put deodorant on my heels before I put them on and I'm certainly not doing four miles. They are comfortable and light and my feet don't sweat in the Florida heat. I like them, i would just suggest a slower breaking in period than I tried.