If you said to me things like ephidrine, or other illegal stuff then I'd say the number was a bit higher than 10%, but I think lower weights there really would be no benefit in taking steroids, you don't need muscly arms to hit hard, strong but not toned, power comes from the health of the muscle too and steroids aren't exaclty great for muscles, it makes them swell and makes the osmotic balance or some shit like that get messed up.