I am from a Ford Family, and love American cars. I needed to replace my 5.0 Mustang preparing for a baby, and no Ford 4 door was available with rear drive, 6 cylinder and manual tranny. Acceleration is a little slower, but still entertaining. From every other standpoint, there is no comparison. I do SCCA autocross events, and this car is a serious performer. Handling is tight, predictable, and confidence inspiring. Ditto the brakes. The 10 year old chassis feels tighter than most new American cars I have recently driven. The chassis is so finely tuned, I have learned things about cars that I would have never learned otherwise, like +.5 deg rear camber turns understeer into oversteer.
Performance, Int/Ext Styling and layout, engineering, Headlights. If you are on the fence debating purchase, just buy it. Get a pre purchase inspection done at a reputable independent BMW mechanic. It's worth the $100. Get a car with full maintenance history. Reliability good for last 3 years.
People think you are a pretentious BMW owner. Short tail looks great, but makes trunk opening too small. Parts are expensive at the dealer, but if you are a do it yourselfer, there are tons of sources online that make parts cheaper than Ford. Excellent repair forum can be found at bimmerforums dot com