Mobil 1 might actually make a lot of sense for a factory oil from the manufacturer. Think about it. As another poster pointed out it's not good to run synthetic oil in the early stages of engine life so mobil 1 allows engine molding for optimization yet provides longer life.
Also, it's been suggested to me that when a car manufacturer recomends a longer time between oil changes it due more to a car leaving a smaller carbon footprint than oil viability. Think about it. There's two conflicting interests when it comes to the modern car: environmental impact vs performance. Oil companies want you to use more oil yet they are forced by enviromentalists to clean up there act so they claim longer viscosity. Yet engine wear and technology has not really changed in the last 20 years or so, so changing your oil less is probably not a good idea. Lighter synthetics offer a great way to make money: they seem more efficient yet more oil is used in burn off.