The X-S-1 is by far the most comfortable on the feet sandal I've ever worn....  I have Teva Mush, some Nike Softgel thing, and another pair of Reef Fannings, and the xs1's blow them all out of the water.  These fit perfectly on the foot, combined with the soft foam like top, the plasticy bounce back heel support is amazing.  It has rubber stopps on the bottom so the sandal doesnt slip and slide all over the floor.  I recommend ordering your foot size, unless you are a .5, then order the number higher ( you are a 9.5, order the 10's).  You will not be disappointed one bit.  Don't forget the bottle opener on the bottom!!!