[Skidz]

Steve,

SBEC and UBEC are the same beastie design-wise. Both are switchmode.

Linear v Switchmode - Linear input is pretty darn reliable by design but work at retricted voltages and lower efficiencies. You need to get one that suits your set up (3S, 4S, 5s, etc). Switchmode operate over a wide battery voltage range (2S-6S) and allow freedom for battery upgrades - but the switchmode is less reliable than linear (but I not saying they are unreliable).

I actually use the BEC output from ESC in my Logo. It is internally independent of the motor electronics (15A output) so the only scenario that would leave me in deseparate trouble is a total battery failure. I guess that is possible but you can have that happen on independent power set-ups too.

There are other options coming through now. You can "HV" rated receivers which allows a 7.2V LiPo to be directly connected (which is 8.4V when fully charge BTW. That is where most guys come unglued when they think "my 2S LiPo is 7.2V. That will work!". No.

The other option being widely used is LiFe batteries which charge like LiPos and have excellent power density but do not have high cell voltages like LiPos. They will sit around 6.6V which means you can direct connect a LiFe pack straight in to your reciever and servos without issue. Very reliable. Lots of places selling LiFe batteries.