Thanks for responses. The M is my daily, and I have perused the Winter thread. After speaking with **********s for a few days, it sounds like the only 18x8.5 ET20 wheel they have and sell in sets of 4 is the Miro 111, which I previously hadn't considered, but like in matte black now that I've seen a few pictures.
I don't think APEX offers the Arc wheel in smaller than 9.5" width, and the Miro set is less than $900, so I think I will go with that.
Haven't seen any pictures of matte black 18s on an e93 M, but they sure look good in 20" with a drop!
m w/ 20s:
non-m with silver 19s: