I reviewed the Sundowner Formula 1 for RCU. I flew the plane with a Saito 180 4-stroke. After the review was published I got into several arguments from other owners of this plane because they said that what I reported as the flight characteristics was not what the plane really flew like. This discussion went back and forth until I figured out that reason. They were putting huge engines on this plane (i.e. 45cc, 50cc, and larger). This caused the overall weight of the plane to be higher causing higher wing loading. This is what resulted in the differences in handling between my plane and theirs. This extra wing loaded turned a plane that was very easy for an experienced pilot to fly into a monster that would reach up and bite it's owner with very little or no warning. IMHO this is one plane that does not benefit from putting a huge engine in it. If you look at my review you can watch the video of me flying it. You can easily see that this plane flies extremely fast with the stock engine (Saito 180). I sold this plane to a buddy that has the Evolution 35 gas engine on it and he has very similar performance as to what I did. There is no need to stuff a huge power plant in this plane, IMHO. You'll enjoy it more with the recommended power plants.

Ken