Review (5/5): Great results!
Top pic is before, bottom is after the 5th day of treatments. (8min x 4 each day).
I took these pics in the exact same place in my bathroom, in the exact same lighting.
I've used whitening gels & trays before, and my teeth aren't nearly as sensitive as with the other stuff.
Also, the product details say that 1 "tube" of the gel is enough for 4 treatments... well, I got 8 treatments out of each tube. Needless to say, there is plenty of extra gel.