I just have to say these are WELL worth the money... I've only used 1/2 of them and my teeth are NOTICEABLY whiter... I was going to call the "satisfaction guaranteed" number and get my money back either way but they work so well I'd feel guilty!
2 complaints... theyre a pain in the ass, you can't eat or drink for 1/2 hour and you talk like a retard with them in. Also my teeth are a LOT more sensitive. But at least they're white.