Mamba Max internal BEC limit?

[BrianG]

The fact that some will run on 5s and some won't suggests to me that they are running VERY close to their maximum ratings. Even the ones that are currently running are probably being pushed and will shorten their lifespan.

And yes, 3s will work using the built in BEC - but only if there is a fairly low current drain. At a moderate servo load of 1A, 3s will produce over 6 watts of heat on the BEC ((11.1v - 5v) * 1A). Doesn't sound like a lot, but it is on such a small device. Just like anything else; you might be able to get away with it, but is a $140 ESC worth risking when a UBEC can be had for as low as $10-$15? That's up to the individual I guess.