Cheaper and more reliable than a BEC is just using 2 diodes in series in the power cable, it will lower the voltage by 1.2~1,4 volts. Just find a diode that can handle 5A or more, otherwise a simple diode bridge rectifier is also a solution (if you look close it has 2 parallel lines of 2 diodes in series)

Yeah, well, the $20 regulators aren't exactly constant.

If you want to be that picky. Use a Hitec servo on straight lipo.....say 2000mah+ reciver pack. Low amp draw servos ain't going to make the supply bounce much.

It's just a complete non issue with quality gear.

All the rulesets I've seen ban running auxiliary batteries.

If you're running a 2s electric car, connect directly to the ESC's + solder post.

Cut the red wire in the ESC's servo wire, and move it to the solder post.

Been there done that. Many 1/8th E racers with obsolete 6v ESC's are doing this. Direct connecting to one of their 2s lipos (the one with the negative wire, for 8.4v, not the 16.8v side). So that they can properly power up a modern servo.

It depends on the applications. I have vehicles with multiple servos, multiple LEDs, winches, fans etc. BEC is the best option. Direct power is a good option as well but sometimes extra lipo pack is not easy to fit in the build

Depends on the car. But all of my underweight cars have ample room.

For 2wd buggy and such, no room needed. Just pull power from the main 2s pack. I've used an Rx pack for ballast weight. But it's kinda meh, now that Tekin ESC's have a 8.4 output. And lead weights are lower CG.

My E 1/8ths have room, but I only use a maxed out BEC built into the Esc, because they're over weight. Bad idea adding another component.

But a 50cc airplane, has a seperate lipo for the Rx, and often another for servos. Sometimes 2 batteries for servos. Some surfaces critical. Some aren't. Failed retract servos have killed many power systems.

Some guys use multiple BEC's, or complex power supplies. Some just use multiple little lipos.

None of the above is redundant. We just dont want 1 failed servo, browning out the whole aircraft.

We used to run tiny 800mah lipos in nitrobuggy. But since theyre lighter now, a 1500+ makes more sense.