I'm leaning towards RWD-- Rear Wheel Drive. I am thinking that the RWD gives a sportier feeling, with less weight in the front, not to mention the thousands of dollars less cost, and the greater (GREATER) fuel economy, with RWD only-- unlike adding AWD to the Model S, where AWD gives more fuel economy. We had a loaner when the wife's S90D was in for 2nd year's service. It was an 85. It seemed so much sportier! I think it was because it did not have that heavy motor in the front. I've been waiting for this Blue Star since 2003-- before Elon Musk was with Tesla. I put up solar panels in 2001 or 2002, then looked for an electric car to run on my sunlight. RAV 4? Not much to choose from then. But I heard about Tesla. Martin Eberhard was making an expensive sport car, then a luxury car-- then a Blue Star!
RWD means you'll get your car fast! You should just try to go for a test drive as Brea has like 24 vehicles available for it. They have the P and the RWD, so just be careful if you test the P you might get the urge to splurge. Good luck!
Driven both the M3P+ and my current M3RWD. Yes; you can feel the extra 250 lbs, but the larger staggered 20s make up for it mostly. I don’t think I would own the M3P with 18s.
I don't think the 20s are giving you as much performance as you think. It's probably mostly the better tires they come with.