Let me tell you..
This thing is expensive, but worth it, especially if you factor in the cost of professional teeth whitening. I know this because my mom works at a dental office. Initially I was hesitant to try because my past experience with in home teeth whitening trays always left my gums red and painful in the days that following. It's now been about 3 and a half weeks that I've been using it and so far no issues. I use half the recommended gel amount and apply once or twice a week (depending on schedule), but no more than that. It does the job at a fraction of what my dentist would charge me.
Rating: 5 stars