I had my '08 E92 M3 Coupe Jerez Black/Fox Red for nearly 3 years. Sold it last summer.
I had no problems with it at all. The 3rd service (around 32K miles) is expensive at around £800 (main dealer). My car had done 43K when sold and still had the original pads/disks with I-drive showing another 9K miles before they needed changing.
All in all very reliable!
On Order: F80 M3 Black Sapphire/Sakhir Orange.