This is a great car. It drives, handles, and feels like a unique, solid performance sedan should, yet it is smooth and quiet and gets respectable gas mileage. When considering a BMW, please remember that it is not a Japanese car; it won't be as reliable and as simple to drive, nor as cheap. Conversely, you'll be reminded it isn't Japanese every time you drive it -- it's that enjoyable. Maintenance is also more costly: air filters cost $20, it takes synthetic oil, and even special windshield wipers. You should be aware of this before you test drive. My wagon has had only minor problems: door latches and a sunroof drain issue. I love this car -- I wont buy another brand.
The overall atmosphere of the interior; the cornering; the smile-producing acceleration; the heated seats; the BMW rechargeable flashlight; the Central Locking System; the Freeze Warning; the airplane-like panoramic view of the road; the steering feel; the solid "thump" when a door is closed.
More horsepower would be nice. Also, some more storage up front.