Depending on the year you buy, the options will be different.

07, 08, 09 issues are more likely worked out and common place where the dealer is not stumped, also more reliable parts are already manufactured for these years.

If I were you (my opinion) is look at all the features and make a list of need vs want. If your pocket got all the needs then get the wants by most wanted.

What you don't want to do is buy and then regret, at the end of the day you are paying for it and have to deal with it.

my 2 cents....

I have a 07' 4.8 decently loaded and no issues....

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2007 X5 4.8 |Space Grey | Sport Package | Cold Weather Package | Premium Sound Package | Active Steering | Rear seat entertainment | Premium Package | Rear Climate Package | Technology Package | Comfort Access | Multi-contour seats w/lumbar | 3rd row seat | iPod and USB adapter | Running boards | Wheels Arches | 214, 20" Wheels |

05' Mercedes S55 ///AMG
05' 745 IL (Sold)
01' 740 IL (Sold)
04' Yukon Denali