He can be dominant, but needs to be in the right situation, much like Suh is in. Suh has some studs on the d line with him that free him up. If clowney is the only player on whatever d line he ends up on, he will be double teamed and shut down.
I bet Clowney flames out. Look at what he has done since he became a star. Played mediocre football and ran afoul with the law, twice. Imagine what he will do after he gets a signing bonus.