I can only speak from recent memory. After watching the two Barcelona games and the two Juventus games, the guy is good but nowhere near as good as their fans make him out to be. Well above average CM, but not "great". Yes he would of probably attracted interest from medium-big clubs (say Spurs) but no more than that. He's solid, good for us as probably an upgrade (though only a slight one) on Cork.
He might be in the future, but to say he is world-class right now is absolutely ridiculous.