I'm using the Royal EVO 12 in my Skymaster Gripen, I've never had any problem even with synth module and 12ch synth receiver.
I choose Multiplex because is the only one with channel check included, so when the Radio receive the same frequency the Transmitter won't start signal: It's a unique feature, and is very useful in case of crowdy clubs, nobody can blame you if a model falls down!!
Another feature I like is that transmitter has 6 cells battery, so lighter than many radios, and is very simple to use and program.
I think is a very good value for the price you get it!
Just check to have the latest 1.40 software installed in the radio..

Alberto