I have been flying these things for around 45 years now, and moved from glow to gas around 15 years ago. I have not even owned a glow plane in the last 7 years or so because the pure fun factor of flying a giant scale over glow is just worlds apart. Do they cost more; yes, are they a pain in the ass to haul around and setup; yes, do they fly better; yes, are they easier to fly; yes, do they make more noise than a glow powered aircraft; they can easily be setup to make less noise than a glow engine, are they more dangerous to fly; no, not at all, any airplane large or small in the hands of an idiot is an accident looking for a place to happen; size has nothing to do with it.
If you have a loose cannon at the feilds you fly at; then I would suggest in the best interest of your clubs; reel the rebel in, and make him understand what could happen to your flying site. Now keep in mind that just because a pilot is into 3D flying; that does not make him a rebel that is reckless...
Bob