Not outdated in my opinion. The lines of the E53 are timeless and it is similar to the E39 in having a "classic" BMW look. I only moved on from these cars as I feel the E53 demands unusual amounts of time and $$ to keep on the road.

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2016 GMC Sierra 2500 HD All-Terrain, Duramax 6.6

2011 X5M Alpine White/Sakhir Orange, Eucalyptus, Spare tire!, Comfort, Soft Close, Tech, Rear Climate, Individual dash, Individual Audio, HUD, DVD, USB, Cold.

Gone:
2008 4.8i
2005 X5 4.8is
2004 X5 4.4i Sport
2004 X3 3.0i 6MT
2002 M5