Stanford ran a 3-4 defense and Fua was the nose tackle.
Fua can't anchor a 4-3, much less a 3-4. Not in the NFL.
Let me be the first to say, I do not think DE is a top need of ours.. however, I think Coples would be a drastic upgrade over Hardy in terms of run stopping and I don't feel we would lose anything in pass rushing.
I'm not of the camp that believes Coples would be much (if any) of an upgrade over Hardy. I think people who think Hardy is a liability are just looking at sack numbers and thinking that tells the whole story for a DE. His only real flaw is that sometimes he over pursues letting a RB get to his gap, but he is in the backfield almost every play and plays the run a lot better than most seem to think. Coples looks good, but he's far from being the sure thing that Peppers, M. Williams or most top 5 or so picked DEs are. I don't think he's even as good a prospect as Quinn was.