i work at a dental office and ive seen the results of strips and our proc.
The strips can have some good results, but they don't last.....or they just don't give you the results you were looking for.
We use an RX whitening prod that you use for 8 nights. with custome trays that you can save and use for touch ups 1per yr. I used it and had excellent results after 3day(so i didn't do the 8nights)
I've made they for friends and they've had great results aswell.
What ever you us remember you can over blch your teeth and need to be carefull how often you blch and for how long....
let me know if you want more info on the prodc. we use