Indeed, M-cars are made for exactly that which does not mean you can just constantly redline the car. It's still a piece of mechanical engineering subject to wear and tear. To keep the V-8 in fair shape for long enough I think warming up your engine well enough before pushing really is truly the most important thing to observe. IMO a good warm-up is more than just driving 3 minutes or 2 - 3 kms! I would say at least 10 kms should be driven without flooring throttle and probably staying below 5000 rpm.
German Autobahns are a treat indeed (at least as long as there's no jam or road works). I enjoyed some open stretches last summer when driving to Austria. Driving + 230 km/h legally is awesome