Due to an old back injury I needed something with more supportive/ comfortable seats that was easy to get in and out of. I tried almost everything out there until I found BMW's X3. The seats and height were absolutely perfect so I ordered the car based heavily on those two things and relied on BMW's reputation for the rest. I certainly was not disappointed. It goes and stops like nothing I have ever driven and if you don't watch your speed it will easily creep into triple digit territory. It corners like it's a car and although firm, it rides like a dream. The fit and finish is top notch and the cabin is quiet. It has great head and legroom and everything is where it's supposed to be.
Comfort, speed, braking, handling, fit, finish and quality. The silky smooth engine! It has a spare. It can tow 3500 lbs. Gas mileage for a 4000 lb vehicle is great (I seem to average about 25 mpg no matter how I drive it).
Other than better iPod integration I can't think of anything.
My wife was tired of her Camry and wanted to sit high in traffic. Looked at the RX350, the E35 and even the new GLK, but nothing matched the driving dynamics of the X3. I don't even like SUVs, but I really enjoyed driving this one. Brakes are even stronger than in my Mercedes, and perhaps the best highway ride of any car we've owned. Only complaint is the stereo controls are small and look alike, which is a common problem in BMW interiors. We got a very basic X3. Vinyl seats, base stereo, no nav and no option packages. Ours has the automatic, heated front seats and privacy glass; no other options. What is amazing is that even without any of the packages the car looks and feels great.
Handling, acceleration, braking and ride. Interior is extremely well designed.