My current one came on 108s like Jamie's, but my previous one had 135Ms - both are 18s.
But I do like 106s and 200s, even if they are 17s.
107s are also popular, as are 32s (even if they are an E46 wheel).
Hopefully this may help:- https://www.alloywheelsdirect.net/bmw_alloy_wheels/z4_e85_alloys