To me, he doesnt move as fluidly as you'd like a DE to be. Perhaps he's just a power guy and that's what I'm seeing. I don't have a professional football eye, but I have watched a lot of football in my time. He just does not move as quickly as you would like a stud DE to move, does not seem very explosive.
He could very well turn into the next JJ Watt, take what I say with a grain of salt, just some observations from an armchair ameture evaluator of NFL talent.