Vorsteiner V-FF 103 Fitment Questions

[theultimatej]

Been searching all over the forums, but can't find exactly what I'm looking for. So I'm seeking the help of more educated people then me on purchasing some 21" Vorsteiner V-FF 103s for a X5M. Trying to figure out what the maximum size I can put on without any fitment issues. Just tuned it to Stage 2+ and was hoping to get some more rubber on the ground. Still want to keep Michelin Pilot Super Sports tires or AS3.

Front: 10x21 ET 40 has anyone ran 10.5?
Rear: 12x21 ET 38

Would 12 fit with that offset? I know BMW had an OEM tire spec at 11.5x21 ET 38

Thanks all.