I already own one pair and have now ordered a second pair of Cali Women's Tone-Ups Meow Wedge sandals.
It is true that there is a wee bit of a break-in period for the material that is in between the toes.
I am a patient person and it is well worth the very temporary discomfort.
Whether or not they actually help you to "tone-up"; I do not know.
They are soooo comfortable that I do not really care whether or not they assist in toning.
I love the cushion that that these sandals provide. In the past, I have rarely worn flip-flop style sandals due to plantar fasciitis. These sandals are not only cute.....they prevent my feet from taking a pounding.
I even wear them at home while walking on the treadmill.
If the price is a barrier; watch for clearance styles. The first pair that I purchased was from JcPenney for $9.95 and the second pair that I have just ordered through Amazon came to only $22.00, including the shipping costs.
They are worth it.