I have not seen the GP CAP 27%, but I have a Hangar 9 Edge of about the same size with a 160FX, which is ample power for aerobatics, plenty of vertical although not unlimited. If you are thinking aerobatics, the 160FX would be a good bet, and is a solid, dependable engine that should give you lots of mileage and happy flying. If you were thinking 3D, the 160FX might lack somewhat, which would lean me more to the Moki--which is also a keeper, so you can't go too far wrong with either one. The Moki likes low nitro fuel, which might be a factor in your area.