Hi Dave,

We have used [link=http://www.radiosouthrc.com/closeup.asp?cid=87&pid=86&offset=0 ]Radiosouth's Regulating 5,6V switches[/link],
with these you can use 5cell battery and those dear Futaba digi-servos doesnt cook up .
Good thing is that you can use higher voltage pack and you have steady voltage thruout the flight.
(Digiservos suck sometimes a lot of juice and pack will drain out quickly)

They are light and guys are using them on 2m birds... will be ok on classic as well

Check also Tony's other [link=http://www.radiosouthrc.com/thumbnail.asp?cid=17]products[/link], glow driver's are also good...

-Jari-