I got this car new, blue with the M sport suspension, then did a ton of mods right in the first year to make it unique and just an absolute monster in terms of HP and torque. Lowered, body kit, Dinan engine and transmission mods, Remus exhaust system, 19-inch wheels, subwoofer, bigger brakes, too many upgrades to list. I love this car, the performance is incredible, I have pegged the speedo at 155mph and driven for over an hour at 135mph with the engine staying nice and cool. The 4.4L V8 with custom exhaust has an awesome sound. Having said all that, you really need to be on top of your game keeping this car running well. You need to have a race mechanic that knows everything about BMW.
4.4L V8, transmission, rear wheel drive, M sport suspension, exterior style, solid and precise steering, driver's car
Lots of small stuff: Use metal instead of plastic in radiator tank connections, improve oil separator valve design, improve secondary air system components, improve evaporative emission system, mass air sensor design, precat O2 sensor design, camshaft VANOS control, AC final stage control unit design.