Will they actually make me look more fit? Time will tell. I do the 10,000 step program on a regular basis, and these stay comfortable for at least half those steps; I was surprised that a flip-flop, whatever the claim to "fitness" could provide a comfy walk. I would actually buy more of these in different colors if they were less expensive. I think $50 is a bit over-priced for a rubber flip-flop, regardless of the 'science' behind it. If less expensive, I'd have 5*starred them!

***August 2011 Update: Since initial review, I've developed knee problems and suspect these shoes. Switched to minimalist shoes and no longer wear "cushy" flip-flops for walking--best worn for very short intervals. Still cute, still feel good on the feet, but probably not so good for the knee joint...If you see an orthopedist for ANYTHING, check with them before wearing these shoes.