RS4 is not better than M3 as far as performance goes. However RS4 is one of the only hot sedans with four wheel drive and thats the special thing about it. C63 and RS4 are good copies of M3 and each has their own market and attracts their own crowd of people. Yet almost everyone who is knowledgable about cars will admit that the M3 is the best performance car in its sector of the market.
Regarding the E92 being not as good as the E46 I have to say the E46 was very very good car but the E92 is even better on every aspect. However the E92 is not as enaging and interactive as the E46 but it is definitely a lot faster. Personally i do prefer the E46 but its just me.
Modified CDV/Rogue Engineer Short Shifter/ RE Diablo Exhaust/ Matte Black Grill/Lighted ZHP shiftknob/Stubby Antenna / 19inch gunmetal Neez Super Euro Cross on Michelin