Garay is a far better CB than Demichelis, but Otamendi to me does look an awful lot like a young Demichelis. When he first arrived here he was doing all the moronic things Otamendi does, lunging into completely unneccessary slide tackles on the half way line, hopelessly overcommiting himself and generally going by the baflling "all or nothing" style that La Liga seems to encourage, but he had the experience of playing in the Bundesliga to fall back on, where presumably he defended more sensibly. Otamdendi was rash in Portugal, he's rash in Spain and he's rash for Argentina. His timing is excellent, so he does get away with a lot and people love a slide tackle so he'll always be a fan favourite, but it puts a hell of a lot of pressure on the rest of your defence to cover for you. Maybe he'd adjust in 6 months like Demichelis did, maybe he wouldn't, but I don't think it's worth the risk when we already have 4 quality defenders.