It's not going to ride & handle as well as a 3 series. It's taller (so more wind noise) & with SUV tires. Has run flat tires which are not as smooth as std radials & no spare. Saves cargo room but is just stupid for a off road vehicle. Std radials & a tire repair kit would do a good job instead of the run-flat's. Other than that, I love the car.
I purchased this car for my wife in 2011. It is a 2007 model. It had 50K miles on it when we purchased it. We now have 168K. This one had about every option except navigation (which I didn't want anyhow), and 19" wheels. Ours had the 18" wheels. First, the ///M package is the sharpest looking of all of these X3's. It body colors every component of the car and you don't get the black plastic around the wheel wells. It has been a fairly reliable car, but like any highly optioned vehicle, it has stuff to break. I will try to list everything that has been wrong or I've had to fix. First thing to go wrong was the sub-woofer under the passenger side seat went bad. Then the right hand door speaker followed. The right mirror doesn't fold any more, nor does it self-dim or heat. I assume it's a power problem. The valve cover started leaking and the CCV diaphragm (built into the valve cover) went bad. That requires a new valve cover to fix. Also lost a water pump. They are electric, so a new one installed was $900. Next was a starter and alternator, another $grand to replace those. The transfer case has a motor that has a gear on it; it went bad. I saved a bundle by replacing the gear myself. BMW doesn't carry "just a gear" for it, but some ingenuous person makes them and I bought one. BMW wants $900 for a new motor. The right hand door seal has leaked under hard rains forever. It gets the carpet wet at times. It's a poor design. I had to replace the rear door vapor barrier as it too was getting the rear carpet wet. The bolster heater on the driver's side seat burned through the leather and burned a hole my wife's nice North Face jacket. I hear it's a common problem on BMW's that could have been disastrous. The ambient temperature sensor hasn't read correctly since day one. It is always off about 7 degrees. One day the left dash side window defroster vent just popped off. The little prong that holds it in just broke off. The washer jug fluid motors both went bad. They would leak all of the washer fluid out. The pop up washers for the headlights quit working. No loss there, I hated the things anyhow. My wife loves the car and wants another one. When she starts fixing it, she can have another. I'm thinking Lexus RX350 next time.
How fun! Shifting into sport mode makes this car fun. Lots of compliments. Has a surprisingly nice growl in the cabin when accelerating. Love the panoramic roof and leather interior. I got mine used....bmw owners generally maintain their cars above average so if you can find a low mileage model just out of warranty, snatch it up and you won't regret it.