I maidened my Harmon Rocket two weeks ago. I have an os 46 fx on mine, with all the servos in the designed locations, with the receiver battery mainted under the fuel tank. I started with an 11x6 prop, but was not able to get much speed out of the airplane (even downhill) and will be trying different props to get more speed out of it. I have read a lot of complaints about the landing gear being soft, but I did not have any trouble with mine.