I bet that was a LOUD birdGood advice! Always try to use an engine thats rated for 1/4 more hp then you need. So at cruise it is at 3/4 of its maximum output. Especially 2 strokes. I am a definite proponent of 2 strokes and have successfully flown behind them on that principle for many trouble free hours. I use as an example my Hummelbird that I flew with a McCullogh engine rated at 72hp @4200rpm. The Hummelbird flies fine on a 36hp half VW but must run at or near full power. and there are plenty documented engine failures. Not that the Mac has a perfect record, but most 2 stroke failures are traced back to quitting under full power or right after being run full power and having the throttle shut off creating a lean condition. But I ran the Mac at 3800rpm cruise without taxing it and never had a problem. Point being never plan on needing a 2 strokes maximum output and you will good!