To me he doesnt seem like a player that really fits the style of play needed to compete in the PL. Three years is a long time away and when he was in the Arsenal team it wasnt as if they were competing for the prem, they were still only looking at top 4.
If we play him centrally in the middle of a midfield what happens when he comes up against the destroyer types? wed absolutely need to partner him with a combatative CM such as Bastian or Strootman, could we, or would we go after all three? unlikely. So say we do sign him we cant play him in his favored position behind the striker, because no matter how good he is, he isnt as good as Rooney there nor is he going to displace Mata who we already struggle to shoehorn in.
Lets assume that LVG will adapt a 4-3-3 the only position I see him in is yet again behind the striker, but thats where we have plenty of players, play him on the left? he looses about 40% of his quality as hes not the quickest player, we have Kagawa and hopefully a new winger who can beat a man. Perhaps we play him as one of the holding players in the middle three, but as we know LVG likes a distributor, a box to box and a no.10. No.10 taken, Rooney or Mata. Box-to-Box, not Fabregas, doesnt havr the industry and is relatively weak defensively. Distributor? maybe, but in a midfield 3 you need all players to double up except the no.10 (the most forward of the three) Strootman with Bastian makes way too much sense, stick Rooney at the tip of the middle three and your talking world class (winning the ball back, distribution to the attacking three of RVP, Mata, and the mysterious LW).
Sorry to go so in-depth but thats my view on the situation.
Id be very happy if we got him, but I would question where he would play and who we would drop.