A good thing is just that .. a good thing. Ferrari owners don't say there's just too many Red or Yellow Ferrari out there so lets custom order a metallic..
The only other worthy White M3 is the Brilliant.. I wish BMW went with Brilliant instead of Mineral, as it is very grayish and dulls the sportiness of the car. If you have an AW and want to have the MW look, just don't wash the car and keep it dusty.