Actually it was deemed to be a bunk supplement....but more research was done on and it showed that it has more benefit if you take it long term. So the longer you take it the more benefit you'll see out of it. IIRC, the daily dose was 3-4g.
I am currently running hmb at 3g per day in either eas reload or armor, I started taking it for basically wound healing, since that is what we use it for at the hospital, in the form of juven. I believe that it has accelerated the healing of a nagging lower ab injury that wouldnt improve for months. I have been taking the HMB for roughly a month 1/2, improvement is vast! As for performance increases, cant really say much.