RE: .15 size planes
A Sig Colt was my first RC plane. It had an Enya .15. It says a lot for the plane that it survived seven or eight flights as I tried to teach myself to fly (I later learned on a buddy box with an Eagle 63). There are a lot of 1/12 scale combat designs floating around. The smaller ones with inline engines (mustangs spitfires, messerschmitts, migs ect) can make nice flyers on a .15. I still have a Colt wing someplace but couldn't find it the last time I looked for it.