Sixty bucks is a lot for a pair of flip flops.  Still, I got a pair of the X-S-1s because I completely wore out two pairs of the original Reef Fannings.  The X-S-1 is very similar to the Fanning sandal, even including a plastic beer bottle opener in the sole.  The original Fanning's bottle opener is metal.

The X-S-1 sports a thicker, more high tech heel area.  It's like that plastic trampoline style heel that Nike pioneered with their Shox and many running shoes have a similar design.  This makes the X-S-1 have superior heel cushioning and support compared to the Fanning.  The forefoot design and thickness is exactly the same as the Fanning, however, and that's the area in which both sandals are lacking.  Because the heel is taller in the X-S-1, it also gives the wearer more of a sensation of wearing heels.

If they had just given the X-S-1s another 1/4" or so of forefoot padding and thickness, they would've had a winner.  As it is, it is easy to stub your toe in these thongs because the forefoot area under the toes and the ball of the foot is so thin.

Still, this is a comfortable thong to wear.  It's better than the Sperry Topsider Santa Cruz in many ways, but it is not the best high quality thong for extended walking.  That award goes to the Teva Katavi, which is, for me, perfect in almost every way.  It's also significantly cheaper than the X-S-1, if not as high tech.