No, not a lot, only highways in Germany AFAIK. Where I live the limit is 120 so 150 is always over the limit. Road fatalities in Germany are the same as in my country because in Germany you also have idiots driving 200km/h. What you have to do is adjust your speed to the conditions. Depending on how the roads are build the limit will be different but if you're driving 50km/h faster than everyone else you're creating dangerous situation. Same if you're driving too slow obviously.