PBM is a BIG re-boxer. Just about everything they sell, is bought in bulk and re-packaged. PBM Power pistons are Mahle, PBM Power seal rings are Mahle, the roller lifters are all Morrell, the cranks are all Scat, the rods are all Scat, their rockers are Yell-Terra, and on and on. I buy a lot from them, because they do have good prices, and, I know its all name brand stuff. The only thing, is, with the cranks that I have found, is, they don't balance as easy, as a crank that came in a Scat box. I know that sounds weird, but its possible, that they missed the bob weight target somhow, on the PBM boxed cranks, and thats why they are sold cheaper? Not sure. but usualy, they either need a TON of weight taken off, for your normal stuff, like say an SRP piston, and the H-beam rods, or get creative, otherwise you need to add weight, which, say for example, on an Eagle crank, with Eagle H-beams, and the same piston, its usualy a minor amount.
Frank