I've used it. I've heard really good things but it didn't do me much good. Thats probably because I didn't use it right.
I got the mouth spray. You're supposed to spray it on the inside of your cheeks, on the roof of your mouth and on your tongue every 3 hours. It also suggests not to "spray" with an empty stomach. Well, I don't eat every 3 hours so I didnt spray every 3 hours.

Drink Vitamin C and get lots of rest!