I just watched some highlights during his career and I took away two negatives.
1) when he faced LSU, a NFL style defense in terms of talent, he was 18 rushes for 54 yards. Not overly impressive.
2) He looks less explosive in 2011 than he did 2009. It's probably the wear and tear on his body. Did he accumulate too many miles in college?
With that said, he shouldn't be the feature back, so that would probably remedy some of my concerns.