Auxiliary Diesel Tank Gravity Feed vs. Electronic pump

We have a KSH 55 gallon inbed fuel tank and a toggle switch is what is used to change from the main tank to the inbed tank. We had it custom made for the room that was available between the tool box and air hitch in March of 05. Our truck is for towing our fifthwheel and solo driving during the winter so needing to haul items in the bed will not happen.
chevman