Since he's a physical beast, I can't imagine it would hurt him much. The talking heads say he'd be #1 if he was in this season's draft. He can't improve upon that. Maybe, if he sat out, he'd lose a couple of spots due to "attitude" but, because of his physical skills, someone at the top would draft him unless he showed up at the combine, or personal workout, with a big offensive lineman gut.
With the new rookie salary structure, it really doesn't seem like a horrible idea. Of course, players want to play. He's already brushed it off as nonsense.