I think that Bisping is a top grappler, and has a very underrated JJ game. He is overrated as a striker. If he was able to at times dominate Sonnen against the cage and was actually able to take him down, I would bet that he can do to most of the MW division.
He is really good at stuffing takedowns, and is second to none at popping right back up once he is taken down. He really needs to start using his completeness as a fighter to his advantage. He should never try to bang with guys with weak TDD like Belfort or Wanderlei, hopefully he starts to take advantage of his opponents weaknesses from now on.