Check things carefully. Make sure that the trims follow and that you get equal movement withboth sets of sticks. Examples, and this was my experience with Futaba, the throttle would not get full travel on the trainer box, and old 4 channel to a 9C master. I could get from throttle kill to about 6K or if I changed the trim, I could get from about 4K to WOT. No way to do it all. The rest of the controls followed the 9Csetup though. Then I was setting up a buddy box setup for my son's 6exa (I think that is the TXhe has) again with an older Futaba 4 ch. All that setup would give was raw stick movements, none of the trim or any mixing in the master worked when the trainer had the sticks.

Another thing to watch out for, Near the end of my buddy box training, I had landed, taxied to the pits and got to a full idle, but Icouldn't kill the engine. Iask my instructor to kill it and when he let up on the trainer switch, his TX was on WOT and it was an interesting couple seconds. Barriers are good.

Just spend some time making sure that there are no surprises when the switch is transfered. It took me and my instructor a while to realize that the throttle wasn't the same between boxes.

Don