Just to clairify, I was not bashing Rossi by any means. in fact for the past 3 years I have been running a Rossi .45 and .61 in a couple warbird race planes. Most of the time I am having to compete with YS 110-120 powered airplanes. My Rossi's hold their own. At to their manners, after I went through the learning curve on tuning, fuel, props, pipe length they have become the most reliable glow engins I have ever owned. I think is 3 years of racing I have had to pick up my starter 6 or 7 times, the rest was bump started. After about 75 heat races I have had maybe 3 DNFs. That being said, I'm sure the .81 is a great engine just poorly suited for a scale aerobatic airplane.