Hi John,
Buddy box ports tend to be features on more expensive radios, where as most of the RTF electric trainer parkflyers are built to a budget, and hence feature very simple transmitters.
If things run true to form your son will probably pick it up more quickly than you, and you'll be the one who most imperils the aircraft
Training with parkflyers can be done through a combination of:
* Using the simulator (make sure your TX can speak to the PC to use FMS and
* The more experienced pilot flying the aircraft to a good altitude, say 60 feet, passing the controller to the less experienced pilot, and then taking it back when they get into trouble.
Good luck.
Cheers,
Oz.