Regarding the radio, you can get away with the 6i with a bit of work around using some of the dual rate switches to help give you a 3 position switch to activate all the NAZA modes, but it can be a bit tricky especially if you also want failsafe. It is much easier to setup on the DX8 where it has a 3 way switch. The knob on the DX8 is also useful if you want to control the gains or gimbal tilt in flight.