Perhaps, but Gilardino already knows how to finish, and he already is the go to guy, and has more alround skills than most oal poachers like Trez for example. I think that Zlatan and Cassano would more of a clash of similarities than Zlatan and Gila, because Zlatan likes to drop deep for the ball, he likes to take on players from outside the box and roam around the box.
Zlatan's frame is ideally suited, but he doesnt really play like the target man, and IMO his partnarship with Trez was better than the one with Alex, simply because Alex and Zlatan would oftne do the same things and not have a central player around which to play, a a target man. Gial would fit that position perfectly.
I'd much sooner buy Gila than CAssano.