I've always like Dinan.

 

Tubi is nice, Assuming he got an E60 M5 - I like how it retains the factory sound characteristics of the S85 V10, but just amplifies it a bit. Eisenmann race is on the higher db side both in and out of the cabin. Top notch craftsmanship and you can'g go wrong with it. IND, a TS sponsor, and also local in Chicago, can probably help out in this area.

Also consider some exhaust systems are axle back (just replacing the rear mufflers). While some are full header back systems that eliminate the cats for more sound and power. I believe Tubi and Eisenmann still make their replacement x-pipes.

Another really good option is Rogue Engineering and their x-pipe. It retains the stock sound, but just turns up the volume a few notches. It also sheds some weight as well. Less expensive than Tubi and Eisenmann. Just a thought. Heard it in person and it was very good.

If he got an E39 M5 (V8), eliminate the rear mufflers and do straight pipes...best option hands down.

 

I guess he has an E39 M5 since the thread title says "20 M5" and I guess he meant 02 M5
based on that I`d say that he should rather get a good system from Eisenmann...straight pipes will give him some bad drone in the mid rev range

 

Sorry guys, it's a 2008. I think I got the info I need, just need to do some more research. You've pointed me in the right direction

 

We installed a UUC/Corsa on one of our customers E60 M5. It sounds great. Quiet inside the car, loud outside the car.

 

krissieg F1

 

SuperSprint full exhaust system. They offer their exhaust for Hamann.

 

RPI

RPi - Race Precision, Inc.

 

Ok here is my two cents. Active Autowerke
http://static.photobucket.com/player...o/MOV03479.mp4

 

I have heard a few RPI and tubi's and I prefer both of those to the other options. And there is no reason for a sedan to be supercar loud. But they definitely let people around know the car has a v10.