Lots of people have had great results with it. I personally have used it, it tends to make me on the nervous side, and have problems sleeping if I take it too late. My wife on the other hand took it with great success. but she can drink a cup of coffee and go directly to sleep. But, it is not a magic pill. You still need no matter what the store clerk tells you, proper diet and exercise. It is just a metabolism booster to what you are already doing. I found it best timing it to start its effects just as I was beginning my workout. About 45minutes prior to exercise seemed just right. Cycle on and off at the recommended times.