Ive been lucky enough to own both E46 M3 and current B7 RS4.They are both totally different beasts believe me.The M3 is much more "the drivers car" it was a pig to live with every day.The ride was rock hard it was jerky, clunky and believe me the build quality wasnt that good!The brakes also gave up the ghost when pressing on. It was a 2005 car to! Two doors and you didnt dare boot it in the wet or it WOULD kill you!

However i liked it but it was an aquired taste and totally impractical for my two kids but went well and scremed its bollocks off under full chat.Girlfriend hated it.
Now the RS4 is different again, smooth refined build quality impecable.Extremely well planted(i know its 4wd) and practical and it is rear end biased with te 4wd up to 80 percent if required.
Lets not forget we talk about"drivers cars" but apart from the odd trackday i think we all apreiciate we require a car we can use everyday and IMO the M3 isnt that car the RS4 is.
BUT again each to their own.
Ive had two cars Clarkson says are driven by cocks so i,m doing ok!!

Mine wasnt a CSL but i guess thats even worse to live with!!
By the way the RS4 will beat the M3 in a straight line i can say that but not that much in it.