The Powerbomb vs. The Piledriver

Which moves is more devastating?

A piledriver by far, because you are spiking your opponents head into the ground. With a powerbomb, they can lean forward and absorb the blow with their back/shoulders. With a piledriver it's just 2 guys, gravity, a skull, and the ground. This is why piledrivers are illegal in the UFC.

Power driver yes......If stone cold gets hurt from it you know it's bad.

Yeah, a broken neck is no joke. The worst I've ever seen from a powerbomb is a KO (Quinton jackson knocked out Ricardo Arona with a powerbomb in PRIDE and it was awesome).