As noted in the other thread, I too use a Digitrax command station and OG-CB cards with no problem. The only caveat I am aware of is that you have to have compatible current limits: the OG-CB cards trip at ~4 amps, while I believe the Digitrax Zephyr only puts out 3 amps, so the OG-CB's are useless in that combination. However, the DCS100 (Super Chief) puts out 5 amps, so the breaker will trip before the command station does, which is what you want. If you have a Zephyr, there are other breakers that will trip at less than 3 amps, but I'd have to do a bit of research to recommend one.