Bargs certainly makes for an interesting frontcourt complement to Dwight Howard.
I believe Bryan Colangelo recently admitted that Bargnani is not suited to play center, and should be moved to PF.
He's equally ill-suited to play PF with his slow lateral movement.
One of the few areas of the game he excels at defensively is post defense, he'll have less chance to apply that at PF. Meanwhile his help defense and man to man liabilities could get worse....