They get very expensive to keep up with. A warranty is a good idea, but maintenance can also get pricey. Theres also alot of technology that fails that wont be covered by most warranties unless theyre explicitly bumper to bumper like BMW CPO. The non turbos have valve stem seal issues, so consumption is always a problem, and a nice puff of blue smoke after idling for a little is a bonus ha. Were starting to see differential issues on the earlier ones, v8 and the diesels just blow them up. Another customers power rear trunk was inop and shut closed. Both rear power liftgate actuators installed were around $1300. Runflat tires easily $1k installed. Front brakes 650-700 at my shop, 900 at the dealer, (OE Zimmerman and Textar) newer models are more expensive than that right now. Dont even ask about the shocks with the adaptive suspension. Power front sway bars are leaking all the time, always have though since 02 745. Just did 8 coils and plugs on an 11 x6 5.0 last week and we were at around 1100 I think, plus other little [censored]. Overengineering at its finest. I went to school for these models in 2008 and its really amazing what kind of technology these cars pack behind the scenes, and that was almost ten years ago!