Wow, hope it works out for you. He's not dissimilar to Sissoko really, in that he is a physically imposing central midfielder who is more suited to a more attacking role than as a midfield destroyer. How do you plan to use him?
When everyone is fit I'd imagine we'd play a midfield 3 of Gibson holding, Fer going box to box and Fellaini playing furthest forward (unless Fellaini is going, in which case you'd have Osman in there)
Box to box should suit him fairly well. Hope he does well for you. Shame for my hometwon club they sold him for half this amount to Twente for considerably less (5.5 million euros) one and a half year ago.