For Barcelona, I would take Arda over Vidal. You can't say Vidal is a "better player, plain and simple". They're different kinds of players. Kinda like how Rakitic is infinitely better for Barcelona than Fabregas ever was.
Thats an overstatement, Rakitic is no doubt a good player, but he hasnt really done anything special to be hailed as a wc midfielder. Right place at the right time, simply. Cesc didnt do as well as he should have, but Barca would have won the treble anyway, with or without Cesc.
 at people judging Turan's and Vidal's ability by their transfer fees. 