Re: 645/650 vs. E46 M3
I had a 2004 E46 M3 convertible and got rid of it for my 2007 650 Convertible. They are BOTH fun cars. They both perform well on twisty roads. I just got tired of the bumpy ride, especially on long trips on the M3 my passengers would complain that they feel car sick especially when I use to drive to Lake Tahoe (twisty roads). So I opted for the 6er which has the perfect everything from handling with comfort and luxury than and an E46 M3. Good Luck and let us know which you choose.
Proud owner of 2007 Alpine White with Pearl Beige leather 650I Convertible with all options fully loaded Automatic Transmission. She's a beauty!!