He's a good player, no doubt, but there's nothing to suggest he's worth the money, he's not a prolific goalscorer by any stretch. Would have been decent if all the figures added up, although supposedly Stuttgart will sell around £6million, which ain't a lot.
He's probably on a big wage to start, the big Russian sides pay massive wages, and when he moved to Germany, he was quite coveted, Stuttgart did well to get him.