I use 15x7 MTI 3 piece wheels. I never heard of them either, before i bought them from some polish geezer. All I know is that they are manufactured in the mid 80's, they are very light, and really well built, the center caps are cast iron! they have stainless steel rims and are et20 - I used 11mm hubcentric spacers, and 20mm hubcentric on the back. Seems extreme but i didnt want to splash out on dishes just yet as i need to tart up the rest.
There is only a few mm between the Track rod and the edge of the wheel. The et13 offset is a pain tbh.
still dreaming of a 535i though....! however, the fact i'm doing f*** all miles at uni now means it's just not worth it until i finish. will keep the E21, and keep it well serviced still. it was epically reliable this winter. didn't let me down once, even when it was sat outside doing nothing for 2 weeks, covered in snow, looking sorry for itself, it still started within a couple of seconds, every time. didn't miss a beat....was fantastic 