The fact is M cars are still top in all of their classes. They have world class engines, and no other manufacture that makes tuned versions of their standard models modifies them as heavily as BMW M does. BMW is even now developing new M's as standalone models from the ground up. The F80 will look like a 3 series, but is being developed as a unique model from the start. The chassis and body will use a higher ratio of lighter materials than the standard 3 series. Every aspect of the car will be unique compared to a standard 3 series, RS and AMG do not go to such lengths.
The F10m has unique aluminum suspension compared to the standard 5, and its rear suspension is bolted directly to the rear sub frame like in the M3 GTS, also the M5's chassis was modified to allow the motor to sit further and lower in the car. The end result is that the M5 is faster around the ring than a Panamera turbo, and has a much nicer ride...for a considerably less money! BMW asked M5 customers what they want in the next generation M5, and the F10m was the result of what the actual customers wanted, not lounge chair enthusiasts…people wanted a hardcore M3 we got the GTS, people wanted the back to basics entry level M we got the 1M. BMW M is still making world class performance cars.