Took a chance buying a used 2003 X5 4.6 with about 80,000 miles. Have put about 12,000 miles on it so far. Not a commuter car. Best as a hot rod Sunday driver or on short drives to the lake towing 2 wave runners or a boat. Horrible stock radio. You'll want to replace the radio 'head unit' so factor in $500 to $1,000 for that if you DIY. Very nice seats. Fit and finish of interior for 2003 exceptional. Ride too harsh for most people (mainly due to the big 20" wheels and low profile tires of the 4.6is). One thing critics overlook is that this machine was built to tow 6,000 pounds! So much torque and power. Quick 0-60. Snaps your head back in the seat, no problem. More than you will ever use. Could you take this car to 300K? Maybe, if you are gentle. I've heard the weak spot is the transmission. Don't abuse it and you should be okay. It's really a 2nd car for carving back roads on sunny days. It is a high performance car that just happens to be an SUV. I wouldn't beat it up commuting. There are better cars for that job. Oh... and did I mention this car can corner! You can definitely take this car to the track if you like. It can hang some serious turns. It really is an ultimate driving machine if you get it out on the twisties and cut loose. It's like two different cars. Around town it's a bit bumpy and overkill. But in the canyons it drives like a race car. Update 12/05/2017... Still have the car and it's still doing well. If you want to keep one of these long term there are a few maintenance items you will need to address. You can perform these fixes yourself if you have time and inclination; timing chain guides, valley pan, vanos, driveshaft spline. You can Google them and see what is involved. Also possibly gasket behind the water cooled alternator housing. Google them, see what is involved and see if you are up for it. Or, look for a car that's had some or all of these things done already. Not all of them need to be done right away. Just depends on the mileage and how the car was driven. There is also a cold weather oil separator issue fix but those in moderate climates don't need it.
I have this car for 3 months now and I put about 3000 miles including a trip to Myrtle Beach. I enjoy driving this car. My wife loves it and my son wants to drive anywhere we take this car! So far so good. MPG about 20 highway around 17 in the city. I expected better! The only despoilment is the stereo and the fading of all the readout on the instrument panel. For a 50K + car when new is a disappointment! Other then that I very happy with the car. No problems so far other replacing the rear window regulator in the first week! Very easy to do and I was done in 20 min. Shop around for parts. You will find big difference in money. As a used car and paying only 1/4 of original price is GOOD!
Bought used with 20,000 Miles, Loved appearance inside and out. Immediately noted the AM/FM reception in Northern Minnesota was the worst of my experience with over 30 vehicles. Dealer denied there was a problem in 3 visits. Finally told me "95% of owners don't listen to AM anyways". Communications with corporate BMW were very poor. The person in NJ was experienced at deflecting complaints, but knew little about cars. Twice had engine problems under warranty where car blew black smoke out of exhaust. Now at 95,000 the dash displays are missing some digits and the fix is too expensive. One Key Fob is dead and you can't fix yourself, wheels are corroded, dealer experience has been poor.
I have owned trucks and SUVs all my life and I have yet to own one that is as much fun to drive as the X5. You pass other drivers like they're in reverse and it corners and brakes like a BMW should. It's one of the best looking vehicles on the road and no matter how hard you push it, it wants more. However, every other month another sensor or display light would go off or hose will leak or seal break and I'd get hit with another $500 bill (at a minimum) to fix something that just shouldn't go wrong (door locks, airbag light, etc.). It was always something. If you have the patience and another vehicle to rely on, it's a great car. If it's your only car, check your roadside assistance.
I bought my X5 as a certified Pre-Owned from my local BMW dealer. My X5 is my first BMW. I love the handling, acceleration and reliability. It is solid and safe on the road and at freeway speed. It has all the benifits that a brand new one would have. It comes with the 100,000 extended warranty and free maintenance service, so I pay nothing for all services. After the first three weeks of my purchase, I had problems with the lights in the dashboard and the transmission, so I took it for a free repair.