I have been to the World four times, and the first three times my feet were miserable. I wore tennies or dr. martens sandals. This last trip I purchased Teva Circuits, and boy was I surprised. My feet usually got sore on the bottom, and I had to soak my poor, tired dogs every night. Not this time. My feet didn't hurt one day and we were there for two weeks. Even with winter approaching, I am still wearing them, I just found some cool socks. My daughter (19) says they look silly with socks, but I am still comfortable. I wear them every morning when I walk. I don't know what makes them so comfortable, but whatever it is, it's worth every penny. BTW, I got mine at REIoutlet.com for only $45 in August.