11,000 miles on a 2010 X5 diesel and I love it. Excellent build quality, performance, comfort, and zero defects. (I'll be first in line for the new X5 4.0d in 2011.) I like the comfort/convenience of an SUV while knowing that clean diesel doesn't pollute like a gas SUV. I looked at the 555hp X5 M, but I can't stomach guzzling gas and polluting like that any more. No tire problems yet. (And yes, whiners in the previous post, your X5 does have a spare tire. Try reading your owner's manual.) I've had 6 X5s since 2001. Although this is the most truck-like vehicle BMW has ever made, it has the best combination of performance, fuel efficiency, low emissions.
28.5 mpg pure highway (optimal conditions). City/highway combined mpg: 23. That's great for a 5,300 lb vehicle. Add 3 passengers, and it's 3 tons. Comfort seats are the best. The new iDrive/navigation is vastly improved. The torque is great in the mountains.
BMW, pay attention: not all buyers equate noise with performance. This X5 is quieter than the last generation, but you can still tune out more exhaust and road noise. Diesel engine noise is fine but the exhaust note is too intrusive especially on hard acceleration. Your competitors all are quieter.
† Edmunds.com received the highest numerical score in the proprietary J.D. Power 2014 Third-Party Automotive Website Evaluation Study℠. Results based on responses from 3,381 responses, measuring 14 companies and measures third-party automotive website usefulness among new and used vehicle shoppers. Proprietary study results are based on experiences and perceptions of owners surveyed from January 2014. Your experiences may vary. Visit jdpower.com.