The million miles is the goal, and yes i think they both have a good chance. 86% of the way there. The oil change interval is 20K, with Rotella synthetic. I have used Schaeffers when I can keep it in stock. They built good motors at the Indy plant.That is incredible. You think you'll make it to the million mark? I've read good things about that bypass system. I may check into that myself. How many miles do you go in between oil changes with your bypass system, and what kind of syn oil are you using?