1989 300CE with 93k miles - rate a 10. No squeaks or rattles at all. A little wind noise through the driver's window at the rear, but being a coupe without a window channel, it is to be expected. But . . . one thing that drives me nuts is the sound of the fan behind the climate controls. It is always turning and at a stop light, is way too loud for my taste. It can be turned off with the right most button, but the manual says to not use that position for any period of time. With the back of the sunroof popped open, I turn it off anyway.