No regrets with my 2008 X5 4.8i. I would buy it again. Yes, not cheap to maintain but I think it's worth it.

Best advice that I can give you is look for low mileage. Mine has only done 56,000 miles and everything is in great shape.

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2008 X5 4.8i | Wheels: Summer> style 336 20" RFT; Winter> style 214 Ferric Grey 20" RFT | Aero kit | ESS E-Flash tune | V1 | LCI Rear Tail Lights | Coding completed | Engine replaced at 90K