I have worn these for a while now and I still don't know how good they work.
The first day I wore them, my calves felt tighter or achy in the morning. The next couple of days I didn't feel tightness, but I started getting a pain in my lower back. A few days later, the pain went into the back of my legs. Now the pain I was feeling wasn't a work out stretch in the legs, but leg and lower back aches. I decided to leave them alone for a while.
I went back to them a couple of weeks later, and the same thing happened. I haven't worn them since. I think the heel is too hard. I was at a store where they sold knock-offs and I asked what the feed back was on them. The sales person said they reviews were 50/50. Love em or hate em.
My conclusion is the same. Some people swear by them, I don't. My back and legs hurt and that out weighs how tone my legs would get. I think walking around in comfortable wedge heals will give you better results.
Have you tried the Shape-Ups? Do yo think they work or heard they do?