Price aside, the M6 especially this 2012/3 model, based on classification, size, layout and general performance should be compared to the likes of:
Bentley GT/C v8 and maybe W12
Mercedes CL63
Mercedes SL63
Ferrari 599GTB
Jaguar XK
Aston Martins entire current line excluding the One77,(I hear there are still a handful left for sale). The Rapide will be M6GC competition.
The 6 series has definitely moved up market. Failure to understand or see this results in comparing it to the wrong cars.
Feel free to add whatever I left out.
Also the current M3 does well when put against the Audi R8 v8 & Porsche 911.
A friend sent me an email a few weeks back and wrote, "take note of the performance numbers of the three".
http://www.youtube.com/watch?v=Cu7uy...e_gdata_player
http://www.youtube.com/watch?v=__nXs...e_gdata_player