Don't touch them man.. no matter what anyone says. I had one mate spewing up blood on new years eve from them and another had the shakes/vomiting/aches/migranes for the next 3 days after taking 1 and a half...
Not worth it, yuk.
Yeah I know, I've warned my friends about them just incase they get desperate enough and just buy any random thing they find.
Not like it matters too much to me, I know people with white hearts still.