I fly a lot of 4 strokers glow motors, but for applications above 1.2 cu., I'll install a 2 stroke gas motor. I like Zenoah magneto motors. I also have DL's and CRRCs. In my scale applications I don't know why I like using older magneto engines usually conversions from weed wackers, I can usually buy then for 50 to 80 bucks. I do have one 4 stroke gas motor, but it is just for scale applications as it cannot be run inverted for any length of time and it is a bit gutless. At less than $3, gasoline is about the cheapest type of fuel you can get.