Carlos, once again, thanks for the information. Unless I decide to take a chance on one of the "generic" Mustangs from China, it sounds like the WM Spitfire is the best choice. I considered the VQ P40 that was recommeneded, but it seemed heavy, had mixed reviews, and the price seemed high. I am a bit put off by all the mods that are needed for the H9 Corsair. Maybe I'll consider it later, after H9 works out the rest of the issues. Still thinking about the power options, I'd like to use the K&B. I don't think I want to buy a .90 2 stroke. If I get a new engine I'd like it to be a 4 stroke, probably Saito .91.