Very happy with the results I got from their Premium Whitening Kit after about 10 sessions of 30 minutes per day. Big noticeable difference and would guesstimate around 5-6 shades whiter. My teeth got a little bit sensitive towards the end but I did choose their strongest gel. The blue remin gel helped a lot with this sensitivity though. Don't bother with getting your teeth whitened at your dentist/salon when you can do it yourself for much cheaper!