[Charley Rose]

This is a very tough one to answer. They are both more powerful for sure, but both more risky too. Although they are both generally well tolerated in the body and can be very beneficial in various ways, for a minority of people they can both have serious side effects too, which makes it difficult to give you a straight answer. If I had to pick on purely safety grounds I think I'd choose the BO over the PM, although it would be a very close call, but having said that so much depends on the individual person and how each person reacts to different things.