I forgot to mention, you should be able to use the programming functions of the 6XAS if you want. I have a 6XAS as a buddy box.

I like to have exponential on my controls. My brother (instructor) does not. He has the master transmitter set the way he likes it and I make adjustments on my end.

When I fly his planes I usually use dual rates to cut the control throws down some.

Getting your friend started you may not want to do any programming other than what is required to make the controls the same for teacher and student, but it is nice to have the ability to do other things.