In addition to allowing basic switching between command and conventional, doesn't using a PowerMaster offer additional benefits which a switching system like those above do not, such as:
a) allowing both command and conventional engines to be operated via one remote (the Cab 2) instead of having to switch between remote and transformer control - allows you to walk around and control the layout with the remote; and
b) layout can be powered by only one transformer/power supply (one of which you could sell to help offset the cost of the PowerMaster) and eliminates all the extra wiring ?