My experience is with an '02 SMG Coupe. The E46 M3 rides rougher at low speeds than the E9X. I recall that the Dinan suspension was actually supposed improve the ride. They are great road cars with plenty of power and great handling (more understeer than the E9x I think). The engine sounds great from inside the car (contrasting with the raspy sound outside the car). Be sure to change your transmission oil and probably the diff oil too roughly every 30K miles. When the cars were new a lot of people complained about clunks from the rear end/transmission (normal). Convertible owners complained about squeaks and rattles from the top. The Roadfly E46 M3 board was the place to be in the early 2000's. It's a good place to look for comments about the cars.