Just got the 4-door 328i for Christmas, my first BMW. I've had 2 Acuras prior to this car, and the BMW makes the Acura drive like a Ford. It's amazing!! Handling is incredible. Run flat tires make for a very smooth ride. Turning radius can't be beat. Takes tight curves really smoothly, and the acceleration is amazing. I truly LOVE this car, and can't imagine driving anything but a BMW from here on out.
Bluetooth; iPod USB adapter and other electronics; overall handling; comfort of seats.
Cup holders are in an awkward place. Run flat tires are $400 each to replace (according to my dealer). B/C of run flats, no spare tire.