Hi,
I think much of what you were told is sales pitch(BS). A Moki glow 120(20cc) turns 9,000 with a 16x8. A OS 1.08 (18cc) turns 8,900 with an 16x6. These are very high perforance glow engines with rotary valves. A piston ported or reed valve conversion is going to have a hard time competing wih them and they don't get close to those numbers. They also weight almost half as much at two pounds. The sad turth is that a 25cc magnito engine weight almost as much as a 50cc mag engine. If you can see it run it would be good. Don't pay much for it. You can pick up used conversion on RCU classifieds cheap everyday. I don't think that Homelite has made engines that small in a while. Anyway take what people say with a grane of salt.

Dave