All of the .30 sized heli engines seem to work equally well as an airplane engine. Most of the older 40-50-60 heli engines worked well too. The newer generation of heli carbs have been designed for a good rich flight idle on high nitro fuel. To make matters worse most heli carbs are bigger than their airplane equivalent. I have not tried the most modern .30s but I did try the newer OS 50sx-h and it was horribly rich around half throttle when used on an airplane with low nitro fuel.