Easy. Wayne Arthurs and Leander Paes. It's not always size of the wand, it's the talent of the magician. The Pure Drive can definitely be used to volley at the pro level, but probably stringing it up tight would be a good idea if you do. Do I think it's the best volley racket around? Of course not, not by a LONG shot, but in the hands of a skilled practioner you should be fine.
Roddick has stone hands and wasn't exactly a young Leander Paes when he used the POG growing up in the juniors either. He has his style and if you gave him a POG today, he'd still manage to smash his serve something scary in my opinion. It's not like using the POG would turn him into Michael Chang or something serve-wise. Players at the pro level already have their strengths and styles defined for the most part. Once they get to the pros, it's more about little tweaks here in there. A strength of theirs goes slightly out of tweak for instance, and they drop a little in the rankings, a few months later it goes back into tweak, then they climb back the rankings, etc.
As for Nadal? He can definitely volley. Yeah, so he's no Edberg, but then again who is? Nadal is a very solid volleyer in my opinion. I think it's more a stereotype to say he can't volley, it's something that follows all clay-courters around. Just because players don't elect to come in very often doesn't mean they can't volley.