RE: C/L scale handle
I control my twin engine models with one channel and separate servos.
If you did get a radio (with DSC) that had the proper mixing you could sync the engines easily, however since some of my twins use the servo driver (similar to the Clancy Arnold unit) i do the following to sync my engines:
1) Run each engine and set the high speed needle, get an a reliable idle, do separately for each engine
2) Run both engines and throttle back until both engines quit, notice which engine quits first
3) lengthen the pushrod by turning the clevis on the engine that quit first, start with 4 turns
4) restart the engines and repeat step 2 and 3 until both engines quit at the same time, DO NOT ADJUST THE HIGH SPEED NEEDLE SETTING TO SYNC THE ENGINES, changing the length of the pushrod either shorter or longer will speed up or slow down the engine so that they both shut down at the same time. I don't worry about the high end RPM being off by several hundred at full power
If I had to purchase an electronic control system today I would either buy the Clancy Arnold system, Bill Young handle or the JR DSC radio. I did not like the size of the ScaleMaster handle, in fact I prefer to have the servo driver or transmitter on my belt and use a normal stunt handle.