Cringe, you'll really enjoy Moonstone when you finally get your M3 sedan painted in that color. Trust me, I know.
OP and others, I confirm others' remarks when specifying Individual paint color: a dealer with experience will have no trouble getting it done. In my case it took 2 days for order approval from BMW Distribution, then 6 weeks for it to be built (next-month allocation slot was available). I also paid invoice for the upgrade. Also remember that you avoid the metallic paint option (~$500) when opting for Individual.
E39 M5, E46 M3, E83 X3, E85 Z4M, E86 Z4M