Stick 40 - I have 3 of the Gemini Twin 160 and really enjoy them. Not the most powerfull for displacment but sound great. I have run 10% nitro fuels in them for years. I have about 4 gallons of Ducted Fan fuel left over and did a test run with it and picked up 500 rpm. The ducted fan fuel is 10% nitro and a blend of castor and syntheic oil, 20%.

On one engine I am running a Ken Anderson (916-821-2635) "On Board Glow" mainly because the engine is fully cowled. The glow runs all day on two 1.2 amp/hr nicads in parallel.