He'll drag us down if he's a regular. He slows down play, gives away goals with his recklessness and is generally an accident waiting to happen in the games in which he's noticeable, ie not at home against the sides we should be beating.
I'd play him away at OT etc when we could do with another body in there to upset the opposition and generally spoil.
We don't know how well Colo and Mapou will play together so I'll let that one go, but Cabaye and Tiote? Come on, man. One's total crap and the other's never really going to excel in this league, especially not when he has to carry the other.