From my own experience I don't believe filming in the air is worth the trouble. A suction mount on the rear side window works well, but then you only have one angle - yours truly at the controls and perhaps the runway when on final approach. The headcams move around too much. May be ok as a record but I wouldn't torture any third party into watching it. Another camera pointing at the scenery is a good idea but really you need to have someone film from another aircraft to capture what is happening aerodynamically. It all gets very boring after a while - better just to enjoy the moment (if you can while the instructor is screaming at you
). Still photographs are another matter and often have a unique beauty all of their own.