Larry Johnson caliber yes... Shaun Alexander caliber maybe... LT caliber, only if you have the first pick and get Reggie Bush!
Lendale White could fall in the Larry Johnson or Shaun Alexander category. Maroney is neither since he's likely a system back. DeAngelo Williams is more similar to LT than Alexander or LJ, but not as good. If I had to compare him with somebody I'd say he's another Cadillac Williams or DeShaun Foster. He's certainly talented... if he could catch better he'd be a Tiki Barber clone.