If he can't handle the abuse at Leeds, he'll be absolutely crushed in Toumba. But a change of pace could be just what he needs.
Crespo, from what I recall, had even worse reviews from his time in England - if Beluschi ends up 75% as good as he does, then he'll be a solid backup. If we do end up getting the Peruvian guy, we're looking at a lineup of experienced CBs that is five men deep, plus Poungouras and Dimitriou (assuming they're not loaned out).