BEC vs receiver pack

[BrianG]

Other than the two disadvantages you noted, not that I can think of.

Most people grab power for the BEC right at the Deans connector, which can make wiring look a little messy. If you don't mind taking the ESC apart, you could solder those wires directly on the power input on the ESC. You can make wiring a bit cleaner that way.

[jhautz]

Another advantage of the BEC is a BEC will give you consistent voltage to the servos for the entire run. As a Rx pack runs down the servos slow and reduce in power.