From an upcoming article comparing the RS4 and E46 M3 in Roundel magazine:
BMW Club Racing National Champion Ike Nielsen, who races an ex-works E36 M3 and has also owned and tracked an E46 M3, also took a turn in the RS4. I really enjoyed driving it, commented Nielsen. Its a lot nicer and more balanced than the E46 M3 I had. I had to put springs and track tires on my E46 M3 to get it to feel half as good. You really had to throw the E46 around to get it to move, but the RS4 just goes. I was hitting around 140mph on the back straight with the RS4 and the brakes were great. BMW really has their work cut out for them with the E92 M3.