Pretty sure he burned Rashad Robinson or some other big time DB at the last LSU camp. I think his acceleration is ok.
I don't doubt his ability to burn a guy downfield, if you watch his highlights from last year, it just looked like it took longer than expected for him to get into top gear. The kind of hitch that could be a problem if he is jammed well at the line. But then again, that was Soph. highlights, he's probably still physically maturing.
But to catch the ball like that as a Sophomore is unreal. I'm not sure even Dez Bryant looked so effortless catching the football, and he had the best hands on a recruit tape I had ever seen.