I don't see the need for a big car like the F10 when you already got the F12. So to me the F20 makes more sense when you need a second car for daily city driving.
BTW, saw my first F13 today in real life at my dealership here in Norway, looked amazing.
Was a black on black 640d with m-sport and the 20" 373M wheels, and loaded with options., over 1.6 mill NOK.