[Hpirx]

I have the ZTK package with the larger tires and brakes and ordered 18" wheels from TireRack for winter and they fit! I used the 22' G20 M340 xdrive in the configurator. 18"x8 MSW wheels with Pirelli Sottozero 3 225s square. They drive very nicely.

For the OP; I would probably just use the stock square wheels and buy snow tires for them. It's considered a good idea to go down a diameter for snows, but not a big deal if you don't.

I'm not I'm love with the ZTK wheels (893s?).
I think they are kind of blah looking.
13mm spacers helped the look.
I ordered it primarily for the increase in cooling, brakes, and top speed.
The Michelin PS4S tires are ok performance wise, but seem stretched to fit wider tires. I like a taller, beefier sidewall. If I have to replace them I may go up a size 245/255 to 255/265.

If I was considering a new performance set, I would wait to see what APEX wheels is developing for this car. I love the way they looked on my previous m240 and would definitely consider a track oriented 18" set from them.