On the highway I'd rather share the road with good drivers going way above posted limits than with bad drivers doing less than the limit.
Speed doesn't kill, bad driving does.
That said, as mentioned here, respect for others is important. The kid who went roaring down a residential street where pedestrians were present is not a good driver as good drivers don't go out of their way to look for instances that are high risk to themselves and others. Good drivers can enjoy speed, but enjoy it responsibly under the appropriate conditions and in the appropriate locations.
I was driving on I-95 last month - wide open stretch in SC. Posted speed 70 MPH (110 km/h). All the traffic was doing 85 MPH (136 km/h). By "all" I mean cars and transport trucks driving in the right lane with no passing or laner changes going on. In this situation, doing 136 km/h was the safe thing to do if one is a good driver. Doing the limit would have caused the rest of the vehicles to all change lanes to pass which would have been more unsafe for you and them. Agreed?
...and yes, in Germany I enjoy driving fast when conditions and car type permit. Doing 220 km/h where legal is certainly fun if the car is designed for it. Residential side streets are not the place for high speed adventure and good drivers know this. I was driving along a residential steet at just under the posted limit 2 days ago and a kid ran into the street without looking right in front of me. This happens not infrequently. Because I was going so slow (30 km/h) it was no effort at all to reduce speed as he ran by - he was never aware of me before or after, no harm. However even if one is a good driver the simple laws of physics are such that if one was doing over 100 km/h instead of 30 -40 km/h there is no way one could have seen him dart out of a driveway directly in front and stopped in time even if one stood on the brakes and employed the ABS. Reaction time is what it is. The distance between objects would have been covered in a blink of an eye - not even enough time to take one's foot off the gas and move it to the brake pedal, let alone stop.