Some people say that they don't like the mess of glow. Well I can't deal with charging and messing with batteries all the time. I have had some smaller electric planes. There just not the same as glow for me. I do have some small electric helicopters which are good with the electric. If it gets to where I can't get fuel I'll make my own or switch to gasoline.
I see a lot of people who have trouble turning glow engines and choose the right prop to make a glow run good. If done correctly glow is very dependable. I can see where people that don't or can't develop the skills to make a glow run good would get up set with them.