I would look to cool expectations on this lad though. While it's possible I don't think there should be any assumption that he's going to come in and rip the league apart.
Everything I'm reading on him would strongly suggest he's a typical young, talented winger. When he's on it, he's unplayable, but he is very inconsistent and can struggle to impose himself or turn it around if their team isn't on top in games.
I think it's a great signing, but his injury record, and the fact he's unproven at this level, makes me considerably less concerned about it not having a obligation to buy.