A friend gave me a 60% complete Supersportster 60 to finish up. I really didn't want it but finished up up and bought a Tower 61 because it was the cheapest bb engine I could find. The engine started on the first flip when I was breaking it in and has run perfect ever since. I regard it as one of the best of my 17 engines and fly this plane more than any of my others. I also have a couple ST 40 engines I fly a lot and these are also among the best of my engines.