Thanks again for all the details, Breeze.
The M-Sport package (there's no more regular Sport Package for 2013) doesn't do anything for the brakes. I recognize that the 128i has smaller brakes than the 135i, but I'm not going to track the car so I'm hopeful that the stock brakes will be sufficient for day to day use and some occasional hard driving, especially considering the relatively light weight of my preferred config.
Two follow-up questions:
1) Do you know if the additional M pieces are also available for "factory install" (really port install from what I understand) as part of an order? I have to order the car to get a manual transmission anyhow, so I'd prefer just to spec everything the way I want up front and have it arrive assembled, if possible.
2) This may seem redundant given my original question, but I want to make sure I'm clear: you're saying the Performance Suspension replaces all the Sport/M-Sport suspension pieces so there's no eventual difference between starting with a base (non-sport) car vs. a Sport/M-Sport car once the Performance Suspension is installed. Is that correct?
I'll probably go for the new "Lifestyle Package" (hate the name, but love the mineral white exterior and brown interior) which comes with 18" rims (261M on the coupe, I think) and swap the run flats for 225 Michelin PSSs all around.
A 3,300 lb. RWD car with a NA inline-6, manual transmission, upgraded suspension and high performance tires sounds like a proper BMW to me!