Well if both are going to cost us about the same, I think I still prefer Diego. If people complain about Gio being too small, Silva is pretty small compared to a lot of Italian midfielders. I am surprise that hasn't really come into question.
Honestly, I could care less about size. If a player has the ability to do his job and has other qualities that can make up for the physical attributes they lack (Giovinco) then why the hell not?