I can't speak about the engine, but my 2010 e63 has been awesome. I would say the 212 chassis is about as good as the legendary w124. Doors shut solid, nothing feels cheap. The seats are comfortable. The ride on my car is likely a bit stiff compared to yours, but still nice enough to haul the family around.

My car has 65,000 miles. I've only had routine maintenance and a serpentine belt flew off one time when I was doing doughnuts in a parking lot.

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Eugene

10 E63 AMG
93 300te 4matic
07 BMW X3
14 Ford F-150 Fx2