2010 s550- I got to drive it around the dealers parking lot due to my age, ended up buying it. Very soft and blends in with other cars surprisingly well.
2011 s550- Didn't feel special over the 2010 and was the exact same thing so we passed up on it.
2012 s550- 429 hp and 510 ft/lb of torque. Need I say more.
2011 c63- Loved everything about the car, except the brake feel absolutely killed it for me.
I never personally drove a e9x m3 before buying it due to the fact that the only dealer that lets me test drive cars never had it in stock.