Why would Arsenal spend a big fee to upgrade a backup? Anyway, I'm of the opinion that Monreal is very underrated and Rodriguez is overrated. His stats are very nice and his crosses and free kicks very accurate, but he lacks a bit when he isn't doing something spectacular. Not a particularly creative passer (rather just an accurate one), doesn't combine particularly well with other wide players, and he's reliable defensively as well as physically strong for a full back, but he's not exceptional at pressing. He's not a particularly good dribbler either. I don't think he would look as good or rack up the same stats on a team with a more subtle attack than Wolfsburg.