I chose Aquafresh White Trays because my teeth are crowded, especially my lowers, and I didn't think most other products would whiten my entire teeth such that when they straighten out with braces there won't be streaks. But I was unhappy with their dingy color, and I wanted them to be clean and pretty for when my braces went on.
I've now used this product twice, and been very pleased with the results.
Here's what my teeth looked like this summer, before the first round (small, sorry!):
Here's what they look like now, after two rounds (4 months apart):
For a real comparison, look at my lower canine and bicuspid vs. my upper incisors in this pic:
So, I'm pleased. Only my front teeth show and I enjoy seeing my pretty, much whiter smile in the mirror:
The product itself is flexible (kinda flimsy, honestly) trays pre-loaded with a strip of thick whitening gel. You put the trays on your teeth and mush the gel up and around so it covers all the teeth, even in-between. Then you wear them for 30-45 minutes
I still couldn't get good coverage on my lower canines/bicuspids (as seen above) and the very tops of my (long) upper canines didn't get quite as white as the rest. BUT like I said, the teeth that actually show when I smile are *noticeably* whiter and I'm happy with that.
My mom came to visit after the first round, and actually asked me if I'd gone to the dentist to get them bleached. She was very impressed.
There are 14 trays in the box, 7 upper and 7 lower, for an assumed one-week treatment.
However: this product WILL MAKE YOUR TEETH VERY SENSITIVE.
First round I did 7-straight days, and by the end of it my gums were singed and tender, and my teeth ached, and it hurt to brush. BUT within 2-3 days it got better, and I didn't have any further problems.
This time, I did every-other-day over about two weeks and had much less sensitivity. I was able to brush twice a day with my electric toothbrush no problem, and even floss. My teeth might ache slightly the day after a treatment (I did them at night before bed) but nothing really noticeable and it was gone by the end of the day.
So I would recommend this product, just warn about the sensitivity issues and suggest an every-other-day routine. It works well on very crowded teeth or uneven teeth, but not as great on rotated teeth (like my lower canines).