I'm completely happy with mine, runs just like the MFG said it would. That scale diameter prop is just awesome to look at both on the ground and in the air. I have a video of my RCV on my website during break in if you want to hear it run. I was only breaking it in so the video is of it running in my test plane at 3000 RPM. As hobbsy says, it's only noisey in the begining. Once you have a little time on it, you just hear a nice 4-stroke sound and a little gear whine.