Imho. go with the 56mm if you shoot available light and need the 1.2 and if you need faster AF. If you can live with a AF that can be a hassle ( much better now then when it came out ) and slower f-stops, go with the 60mm. Also i find that i like the rendering of the 60mm better then the 56mm. It has a warmer "zeiss" look with a lot of microcontrast, while the 56mm is pretty "muted".
Dagobert got a reaction from Curiojo in Move from 56mm 1.2 to 60mm 2.4