+1.

I also use the GoPro suction cup and duct tape. This method has not failed me yet. I used to simply not bother with tape and had no problems for roughly 2 years (dozens of flights). Then, I had an unfortunate event where the suction cut let go after a bump on the runway. Fortunately the GoPro was completely fine. Fortunately the GoPro did not fall onto anyone from altitude. After that, I realized that the suction cup alone was irresponsible.. From that point forward I always use plenty of white duct tape in a square pattern making sure do it very tightly with no gaps. Seal tape (or electrical tape) is probably not strong enough nor would it survive rain. The tape needs to be as strong as possible. Duct tape and Gorilla tape seems best and I have never had any issues with it damaging the wing surface (gelcoat or poly).

The duct taped mount method is so strong in fact that I suspect it would survive a decent size bird strike. It is extremely secure. Just make sure that the surface you are taping the mount to is clean and that you are (important) NOT trying to suction onto to an area of the wing (or tail or especially fuselage) that has a lot of curvature. I try to use the flattest possible part of the airfoil, usually 65-85% aft of the leading edge.

Happy filming!

Sean