I have highlighted the points I feel applicable from the Mobil 1 website.
Mobil 1 with SuperSynTM 15W-50 is especially suitable for high-performance cars, particularly hot-running or heavily loaded vehicles and special high-tech imports
Notice that different grades are interchangeable, and a multi-viscosity is a more modern oil.
Mobil 1 with SuperSynTM 15W-50 can be used where SAE 15W-40, 15W-20, 20W/50, 15W, 20W, 30, 40 or 50 grade viscosity is recommended.
Mobil 1 15W/50 Flows at -45°C (-49°F), pumps at temperatures as low as many conventional SAE 5W-30 oils
Run a car with and oil temp and pressure gauge in it and your views on oil will change.
(Message edited by peter_c on March 23, 2003)