It's absolutely true that engines are better and oil is better. The humid air that makes it hard to breathe in the summer and the sub zero air in the winter is drawn into the engine by the PCV system and moisture condenses into the oil. If a vehicle is driven enough to be fully warm for a few miles EVERY TIME IT'S STARTED, the moisture will vaporize and get sucked into the intake through the PCV. If the vehicle gets driven a bunch of short trips, the moisture continues to build and a cold engine pushes more combustion byproducts past the rings into the oil. I would rather buy a 5 year old vehicle with 100,000 miles than one with 10,000 miles, lack of exercise is fatal for vehicles, too.