Bent is better in the air than Crouch, he's got a good leap on him and he can actually direct where his headers go unlike Crouch. He wins a lot of flick ons as well. He's obviously very mobile and has proved he can score goals in the premiership, whether upfront alone or in a pair. Why is Crouch joint second? Fucking hell.
Out of them I'd go:
Bent
Gomis
Ashton
Crouch
Johnson