Something else, invest in good quality cells. I made the mistake of buying a set of AA's from Hobby King, to make up an rx pack. Bad move, thinking 2300 mah would be nearly 3 times my old pack's rate.
Cycled them several times to condition them. Then used the pack in a plane I was building. Worked the servos fine, but I couldn't get the retracts to function at all.

These are big ones, with separate JR 391's for each retract. I thought the servos were at fault. Having to fish the leads and retracts out of 4 3/4 foot long wing halves was no joy.

Even plugging the servos straight to the rx had no effect, but I just knew that I couldn't have two bad brand new servos.

I finally got the bright idea to try another power source. Cheap China esc, hooked to a lipo, and both the retracts worked fine.

Yanked the rx pack, voltage looked good unloaded. Put it on my charger and hit the discharge cycle. Not even 15 second at 2 amps and pack was showing near ZERO VOLTS.

Cut the leads and tossed the whole thing in the trash.

Went out to the LHS, spent the bucks on quality cells and now have a nice working rx pack.