I have a 2008 M5 which I am using as my daily driver. I have 25K miles on this car and haven't had any issues so far. I have an extended warranty purchased from BMW which covers additional three years or 100K.
You should try the M5Board for this information. Appears the there isn't much discussion/activity for M5 in the FEST.
2011 Z4 - Space Gray/Black
2011 X35D, Alpine white, Tobacco brown, all options except 3rd row
2008 ///M5 Alpine White
2008 335 Convertible, Monaco Blue (gone 2011)
2007 Z-4 Roadster - Alpine White, Black top (gone 2011)
2006 530 Black black (gone in 2009)