I tried them, used them for a week on and off. I usually was so busy I never used them as often as the directions stated. The only thing I didn't like about them was sometimes the strips didn't stay in place that well.
My wife uses them. She really likes them and they've made a considerable difference. I tried them a couple times, but I'm not disciplined to use them regularly so I didn't notice a difference. They're a little pricey, but they do work.
I bought them and used them for a couple weeks with fairly respectable results. The problem I had is they ended up irritating my gums to the point where I had to stop using them. I should have taken a couple days off when that started and restarted with them after a that short break but never did. The gum thing was the only thing I didn't like, and it could have just been a problem with my case.