BEC vs Rx pack?

[BrianG]

As far as noise goes, the Koolflight UBEC, Hercules HVBEC, and DimensionEngineering UBECs all had noise levels too low for my Fluke to measure. I usually get ~3-4mV of noise, but I get that with the meter leads shorted, so I generally set that as my baseline "0v".

The CCBEC and the cheaper chinese UBECs (even though they are based off the same IC as the KF one) had some level of noise.

It would be a little cumbersome, but you could use a CCBEC set at 7.5-8v, and then a linear regulator IC (LM317T available at RadioShack) and a pass transistor (to boost the current to over 5A) to regulate the rest of the way down to 6v. This might seem a bit stupid, but it does 2 things: 1) filters out the noise since, by nature, a linear regulator "chops" off the top of the voltage where the noise is, and 2) if the CCBEC failed and sent full V to the output, the linear regulator would get hot very soon and thermal - but that's better than toasting a few hundred dollars in electronics! But if the CCBEC works like it should, there is hardly any efficiency losses in the linear regulator because the difference in voltage between the input and output is so small.