One additional consideration about voltage regulators is adding capacitors to the output of the BEC. Best is a combination of a .1mfd, a 1 mfd and a large value (1,000mfd or more). Voltage regualtors are know to oscillate (produce and AC component to the output) and if you look at the spec. sheets, a 1uf is typically recommended or required by the manufacturer to prevent oscillations.
Capacitors are like resistors for AC and the internal AC resistance varies by value and frequency. So for high frequency AC (such as the sparks produced by a motor) a .1mfd appears as almost a dead short.
The 1mfd stops the BEC oscillations and a large value capacitor will act as a voltage reservoir when a motor (such as in a servo) starts to move.
When motors start to move they will draw more current, thus lowering the voltage. When the voltage drops, the required current now increases.
Hope this is of some value.