I’m also on my 4th failed test. I’m going to try the recommended less than a half tank then cold start technique. The tech at the facility told me to look up drive cycle procedure for my specific model. So I’m going to give it another shot.
I was going to do the staggered setup but I chickened out at the last minute. I ended up doing 20” all around. I did the same BC Forged that are on your old M4.
I was wondering the same thing. A bit more top end would be nice. However, I do like the idea of not having to do any major upgrades to the rest of the car.
I was considering doing a staggered setup like you have, and for the same aesthetic reasons, but I was unsure of how it would look. Kudos for trying something different and GLWS.