I highly doubt he would/will reach RGIII's level, or Cam Newton's for that matter.
He's a dual threat in running the ball and a pretty damn good runner, but his passing is suspect at best. And he plays for the Raiders so that increases his chances at failing pretty convincingly. He was an "OK" passer at the college level, and I just can't see him turning into anything special at the NFL level. He'll probably be a serviceable quarterback and nothing more
Yea those guys are just more naturally talented passers/throwers than TP.
Although, I do think that if he went to Oregon instead of OSU he could have been as good a college player. (Well not as good..but still much better than his OSU career)