Watching his HS tape, I have ZERO doubts that he's going to be a good BB for us. I like how he runs within the his offense, and doesn't bounce it outside before he get through the tackles so he can out athlete lesser players on that level. He's running through contact and getting to the secondary level within the play call. That's the traits and type of running I like to see from BB prospects.
I don't think the real question is how good can he be, I think he can be every bit as good as Mills. I think the real question is how fast can he get acclimated to playing BB. Can he transition from standing up to being in a 3pt stance 3 yards from the LOS? Can he get used to making quick reads on how to attack a hole AND playing off the mesh? Can he take advantage the of the cutback once he gets to the LB level and take advantage of those lanes that will give him a chance of a breaking a 20+ yard run? Can he withstand the pounding of the BB on every play, and get back up and say "Give me more!!!"? CPJ seems to think the answer is yes, and he's risen up the depth chart to the point that even with Mills, he was slated to play.
Oh, another thing. He's going to be a weapon in the passing game. He's a pretty darn good receiver out of the backfield. I also think he's more athletic, and a step faster than Mills. As I alluded above, it'll all be dependent on his transition from the offense he played in HS, to the type of running BBs are asked to do in our offense.
Oh, and he'll need to pass protect...