I kind of went through this whole dilemma already regarding wheels for GTS. I knew that I want the 19x11 in the rear, but the front was concerning. Do I get 9.5" and keep the ability to clear suspension and drop the car? or do I 10" rims, then have to buy spacers, bolts, and camber plates.
I too spoke with APEX and was leaning towards the SM-10s in Anthracite... problem was that the front wheels became unavailable within the hour since I last checked it, so that was a no go. I spoke with Geirsen at APEX and he confirmed what the website updated too(
BACK ORDERED UNTIL DECMBER). I cant wait until December since I have two track events in November and one rally in December. Bummer for me.
So rather than spending nearly (plus or minus a few hundred) $3K on a new set of wheels, tires, spacers, bolts, camber plates. I am just going to track my GTS with stock components at factory(street) height. I know this isn't ideal but at least I will set a base line for myself, maybe others. Ill try to lower if I ever get time to do so for track day.
Now aside from waiting for APEX SM-10's to be back in stock, Don't forget the say they will unveil some 19" Forged Rims, maybe EC-7R or SM-10R will become available in early 2021. Yes they will be a little more expensive, but Buy Once Cry Once seems to be the motto around these forums these days.
Honestly, I might get 9.5x19 and 10.5x19 (or 11") forged rims now, burn out the CCBs(Hopefully not), switch to M2C Brake rotors with more aggressive brake pads, and drop the car which would induce increased camber.
Reason being so I can be that guy that pushes harder to get the most out a relatively stock car. This way I show/compete with others out on the track. There will always be someone else putting more pro track stuff into a GTS to make it a GT4, one person who stands out the most is such as one member "YMS" or Ymotorsport on instagram.
Check their page on forums :
https://f80.bimmerpost.com/forums/sh....php?t=1660084
In the mean time, I will be that guy doing the subtle changes to the GTS. Hopefully driving this car to its fullest potential.