on the four-lane high speed HO road course in my loft I have the 30V 10A equivalent just to make sure, because we typically run 18V and sometimes big magnet motors.
somebody mentioned reliability. one of mine arrived with something big rattling around inside and it had no output. I opened it up and found that the big primary-side choke had broken free of the board. after reaffixing it and resoldering its leads, it still works fine to this day.