You think that is sliding
I won't go into details about my night time activities with the benz
here is a video with (I am sorry) not such great auido but it gives you an idea of what a flowmaster dual chamber sounds like with no resonators (subtract a little volume as the camera tunes in on the deep noise and not the top)
Other than subtracting the resonators and chaning the muffler, all else is stock (on the exhaust system )
BTW this is a 617 Turbo 300SD

Benz Movie ~3.5Megs Windows Media

I will try to get some outside the car sound samples...has a nice throaty sound to it...no annoying allergic reaction/closing windpipe sort of sounds