ORIGINAL: gaRCfield
I use 4.8 volts on .90 and smaller planes, 6 volts on larger planes. Larger planes have larger control surfaces, and therefore are exposed to more force. 6 volts gives the servos more power to compensate.
It's the AMPS that give you the force you need
Just like the factory stock TX batteries come out with 9.6 volts at 700 mils.
Might be good for 4 flights.
A 9.6 rated at 1.8 or even a full 2.0 MaH will let you fly all day.
Amps is the power needed for that extra force.
Vegas/