the dealer said. don't drive at the same speed for a long time. Then I asked what is a long time. They said more then an hour. I guess these modern engines actually go through a factory break in. Then they drive them around the factory a bit to get them loaded on boats or trains or whatever to get them to the dealers. Then the dealer drives them around the lot a bit. They spend a long time idling followed by someone driving the car fast then more idling. I have also heard that modern engines are manufactured to very high tolerances and most components wear very little.
I don't know I've never built or rebuilt an engine so I have to go on recommendations. I have owned piles of high milage vehicles and this is my first new car ever. What kills high milage vehicles for me is blown head gasket (saab 9000) or dirty oil galleries (Mercedes Diesel 300 TD Wagon). I'm pretty sure the power plants in modern cars will outlive the rest of the vehicle. (transmission, differentials, body dents and damage, interior)