2007 BMW 3 Series 328xi 4dr Sedan AWD (3.0L 6cyl 6M)
I bought an early 2007 328xi. I have about 17k miles on the car now and it's been a great car. Zero mechanical problems. It has great acceleration for day-to-day driving, and sport mode when you need to merge. Major downsides are (1) gas mileage (20-22 in mixed driving; no where near the EPA estimate), (2) noise from the runflats (the loaner I had for my 1 year service was quieter, which leads me to believe that these tires get louder with age). I also had some paint peeling from the interior driver's side door handle. Apparently almost everyone experiences this. BMW replaced it in an hour, no questions asked.
Exterior styling. Acceleration. The standard lighting package (the LEDs under the grab handles, the lights under the doors, the footwell lights, etc.).
Keep working on the runflats to make them quieter. The front spoiler sits (too?) low.