Regulators are designed to keep the voltage at or about 5 volts plus. Just perfect for all R/c receivers and servos ------- If you want to operate on a full 5 cell pack un-regulated in most cases that's OK also. Some servos don't like upper 5 to 6 volt range that the 5 cell packs will hold, and that is the main reason some like to use regulators.
Lee -------