Does the one hour teeth whitening kit work?

I saw a one-hour teeth whitening kit at the grocery store and was wondering if it worked well. It was around $30-$50. It uses a light and you use it only one time for an hour. I don't remember what it was called but I was wondering if this would work well. If anyone knows of any other good at home teeth whitening kits, let me know. Thanks!
--------------------
I used to use the Crest Whitening strips and that really worked!! You should try that before the light thing, because it's not as harsh I think. My teeth were very white for a long time. I have to use it again...now that you asked. :)
Source