Yes basically that is my feeling. When you add a 4-inch stroke to a motor you instantly add over a hundred foot pounds of torque all of a sudden six or seven pounds of torque that is gained by a dual plane seems not that important. But there's no arguing that a RPM air gap is a top notch manifold. I just feel with that much torque on hand that I would possibly move away from a dual plane and take advantage of the throttle response and fuel distribution of a m1 single plane.I don't think it would be worth changing from one to the other with your particular build I think both if tuned properly would be within a tenth of each other. I ran an m1 single plane for many years and it is a fine manifold! But never on a 416. But I sure wouldn't hesitate.