Review (4/5): Works but painful!
I started using this a few weeks ago. At first it wasn't painful hardly at all. And it's true, after 3 days I was definitely noticing a difference and was very pleased. But the last time I put them on it was so painful I had to take them off after 10 minutes. I plan to go back to them again but am a little leary of the pain right now. However, my teeth are sensitive so this might not be the case for everyone.
Overall, very happy with the difference it has made in the color of my teeth....just wish it was less painful.