I totally agree with this post -- I have many Fox engines which I use mainly for sport flying. The performance of their ABC engines is hard to beat. I have the Fox 40, 46, and a special Fox 74 ABC's and they are spectacular. My Q-500 .40 ABC is as fact as any other brand in our club. I also have a .19 and a .25 lapped Ball Bearing engine and for it's size they too are hard to beat.