Thanks for the very useful discussion. Understanding that I am late to the party and am a newcomer to cnc machining, I would like to note that I broke down and bought the superPID speed controller, which allows the DeWalt router to operate at speeds as low as 5000 rpm without reducing its power/torque by imploying a pwm algorithm. To date, it has worked flawlessly. Expensive, but IMHO well worth the money.