It is indeed quite zippy, but I almost never drive it. My wife is a very conservative driver, and seldom if ever stomps on the gas. She wanted the 550 more because it was the "top of the line" series, not because she is a power junkie.
I drive a GL450, and the ML will spin circles around it.

Back OT,
Thanks to MBDOC and ilovemils for your info. My service advisor finally called me back around 3:00 pm to acknowledge my message to him about the service bulletins. He informed me they had not even brought the car into the shop yet. He kind of offhandedly remarked about the slew of bulletins that are always being issued. Hopefully today a good technician will get to work on it.

David