myostatin- does this stuff work?

Ok guys, so i go into the supplement store today to get a protein shake to down with my lunch, and i start talking to the manager about ways to gain mass. Anyway, this guy walks in and picks up a couple of bottles of this myostatin, which supposedly blocks the gene in our body allowing us to produce more muscle, etc. This guy continues to tell me that he has put on 11 lbs in 3 weeks on this stuff. I would say hes full of shit, except i know the manager and he wouldnt lie about something like that, but he swears this guy looks huge compared to the last time he saw him. I was wondering if any of you have any experience with this stuff, if it works, of if its another marketing hype....Any feedback is appreciated...

I've seen it on the shelf and I wouldn't waist my money. Last I've heard myostatin blocks haven't been perfected yet. I know the FDA couldn't have approved them yet so how can they be in an over the counter product. Not gonna happen. When they do come out myostatin blockers are gonna be the shit but there not really here yet.