RE: Futaba RX's & Servos: NO Lithium Bats, 6v Max??
If you're waiting for Futaba to officially admit that 9252 servos work fine on unregulated A123 cells, it will never happen.
If you're waiting to hear from someone who has been flying 9252 servos on unregulated 5 cell NiCd/NiMH batteries for many years with zero problems........here I am. About a year ago I converted all of my 9252 equipped planes to unregulated A123 batteries, again with zero problems. If you do some searching, you'll find there are lots of us out there running 9252 servos on 6+ volts.
The speed and power increase on 6+ volts is noticeable. After flying the 9252 servos on 6+ volts for years, I would never go back to running 9252 servos on 4.8 volts.