RE: 123 battery setup
Pete,
Nope none at all. I use the 331 for the retract/brake servo and all is fine. I'd say I have 15-20 flights so far this year using a 2 cell A123 (2300Mah) RX pack. AR9000 RX. The 6 other servosare the 3421 digitals.
Dave Rigotti