Danny offers everything Berbatov does -- excellent hold-up play, good passing, nifty tricks and flicks -- but with pace and work rate that Berba doesn't have.
If Welbeck can continue to improve his first touch and become a more ruthless finisher, the sky's the limit for him.
That's the thing...he's a striker....bu doesn't finish as well as berbatov. Not even close yet.
As to carrol. I don't consider him to have good headers for his size, in fact it's remarkable how often he is beaten. He needs to work on leg strength IMO. For vertical.