The little HF generators have quite a following. Things to know are the spark plug has to be replaced with a better one, you should check the tank for shavings and they have a long break in process. I also believe you need to check it for voltage output.
As for hearing it at a Rc field, I flew RC for 15 years and there was always a engine running. I'll bet you most of my RC engines are considerably louder that the generator is. Most are small 2 strokes running at high RPM, the big 2 cyl 4 strokes are a lower tone but man do they sound good. Any would drown out my 3500/4000, that little putt putt doesn't stand a chance.