Has anyone experienced noisy brakes on the SL655

Although you're in the wrong forum to discuss the SL65, the brakes on pther particular models, such as the E55 tend to squeal like there's no tomorrow. I'm sure this is the case for you like it is for many owners of these vehicles here. The squealing can be thought of as being 'normal', unless you want to put an end to it by going to your dealership and request a repair.