He can dribble but I agree his assists and goals are too low to justify the price tag, especially with the injuries.
I like him, he has the potential to be a really good player and if we didn't have several major gaps in the squad I'd be all for signing him. But taking a step back the price, his injuries and the fact that he hasn't yet had a season where he has shown a consistent end product/avoided injuries makes me think we should let him develop for another season at Roma and reassess next summer when he has a year left on his contract.