I think there is a problem with "only one plane system", that only going to work well with the A-10, becasue of the numbers layout. If you change plane is going to be difficult to find the correct key IMO. Even the Hornet and Harrier UFCs are a bit different.
I never try the Buddy Fox, but if I only fly the A-10, seems a very nice product (I hope that they make for the Hornet).
You asked if rotatories works with the radios. You have to check each plane, some have keys to assign, others don't.
Oh, and the Razer keypad, the way you put your hand over it is impossible to lost reference, very different to a regular keyboard.