I have the Digitrax Zephyr and a lot of Quantum Sound equipped locos. Problem is, the Zephyr does not put out enough power to program them. I have heard that there is a booster available for about $50 that corrects this problem, but I'm thinking of just doing a total upgrade and getting the Super Empire Builder, which puts out more power, and comes with an additional hand-held throttle. With the Canadian dollar up, I can get the Empire Builder for about the same as I originally paid for the Zephyr. What do you folks think?