It's loaded with caffeine, which will give you a boost the way coffee does. They've gotten in a bit of trouble for their weight loss claims, though.
If 3 bottles per day burns an extra 106 calories per day, that's 38,690 calories per year. This breaks down to 11 pounds over the course of the year. At $1.49 per bottle, that's $1,642 to lose 11 pounds.