Remus makes a muffler too, specifically for the W126..but it's expensive!! Around 7 or 8 hundred I think. Or you could just put a universal muffler on it, many people have done that. For me personally, I don't think the small performance difference will justify the cost and noise. There will most likely be less of a performance difference than switching from a hot day to a cold day, and then your car will be really loud. I guess it's just a matter of taste, some people want more sound.

__________________
'86 420SE Euro
904 Midnight Blue, Gray Velour
Dad bought it new, now I own it.

"A Mercedes-Benz is like a fine wine, it only gets better with age."