[LSM]

Originally Posted by M6-Coupe

I think OP's main concern was M car, if not and if you think M5/M6 is not DD car so why 650? he can get 640 much cheaper.
And also there are lots of difference between M6 and 650. Since I have experience with two cars (I owned/own 650i M-Sport package and M6) , I can tell you the difference. Beside the aggressive look (front, rear, those big rotors and brilliant calipers) , power, torque, steering, suspension, throttle response, differential and transmission are totally different. The transmission by itself makes two car completely different. ZF8 is really awesome transmission. it's smooth and fast, but not as fast as DCT when you want to change the gear manually or it changes in automatic. overall 650i/640i are luxury cars and M6 is sport-luxury car .... Oh I forgot to say about amazing MDM mode

+1