Yeah, a lot of people have tried it and had fantastic results. It's probably the only supplement out there that can actually deliver on the promise of cutting up while gaining muscle.
Michael Elias is a huge fan of the stuff and has used it many times for contest prep. There are a lot of other natural/enhanced bodybuilders who like it too.
The only thing is, it HAS to be used properly to work. That means following the directions of no anti-inflammatories, minimum omega 3 oils, etc.
On my first cycle I gained like 10 pounds while leaning out and added 50 pounds to my squat. It was crazy.