The unit BMW uses for the M3 is the Getrag 7DCI600. They rate it up to 440 pound-feet and 9000 RPM which is actually even a bit conservative. My transmission took about this torque level without incident driving around. It is the launches and overheats which made it so the clutch packs started slipping. It never fully gave out just the clutch packs were starting to slip and it was not going to get any better especially as I strove to add more power. If launches and drag strip visits are removed from the equation, on the street with a supercharger, absolutely no issues, just like stock. One can even exceed the recommended 440 pound-foot limit if just using it on the street like a normal person. Here is an up close shot of my transmission.