Fit Flops???

"When the FitFlop launched in London in 2007 it became an instant hit and sold 18,000 pairs in three days. These sporty go-anywhere sandals - the brainchild of Bliss founder Marcia Kilgore and Dr. Dave Cook - are engineered to tone and trim your legs as you walk. Described as 'a flip flop with a built in gym,' fans of the innovative fitness footwear include Hollywood style-setter Mischa Barton." -net a porter

So what do YOU think about this "fit" footwear? Would you wear them if they really helped tone your legs??