I had an '01 e53 for 9 years until it was totaled in an accident in '10. e53 was great but I like the evolution to the e70--for the most part I would only would go with the 20s and the wheel arches that come with--a much more aggressive look than e53. Reliability wise, I only have 53K miles on my '08 4.8 so far nothing mechanical has broken down and just couple software updates. My e53 I had little problems with as well.

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2008 X5 4.8
Jet Black/Black Nevada/Dark Burl Walnut
Adaptive Drive
Premium Pack
Tech Pack
Climate Pack
Sport Pack
20" Wheel Option
Premium Sound
Sirius Satellite
Rear DVD Entertainment
Multi-Contour Seats
Comfort Access
3rd Row Seat
Heated Front Seats
Running Boards
3M VentureShield Paint Protection Film