BFG is the same height as Sol Campbell. Taller than John Terry but 1/2 inch shorter than Rio Ferdinand. Height is not an issue but the 6"4 duo of Duffy & Dunk make him look short.
As WA said on the witless, we shouldn't move Duffy to LCB to accommodate Goldson because that is two changes. BFG is just one change as Duffy would stay RCB. Go with Uwe I say.