Ted, Raven,
Herein lies a danger. EFB and GPS systems are complex and it is not difficult to make an error. ... I haven't yet read a safety bulletin suggesting the incorrect use (as opposed to the non-use) of a GPS or ELB to be cause of incident so maybe it is not problem.
I'd go further than
not difficult - It is
difficult to use modern avionics correctly and takes significant training. At RPL/PPL level, students are still getting used to the rate at which things happen - at least "look out and go there" doesn't involve lots of new skills.
And regarding
incorrect use - not so much so at RPL/PPL/CPL level (because most incidents are not investigated) but it seems like every second airline incident is related to incorrect use of FMS/autopilot, or misunderstanding what it is/is-not doing. Again, the technology is not easy to use correctly.
Sure we could have RPL/PPL students using it - but that will take training = time and money.