My neighbor with the propane converted DES CS clone just did an old change at 1400 hrs, last one was at 400 and it looked like it just came out of a new oil bottle. At 1400 hrs today, he said it didn't look quite like new oil but it looked good.
The last 1000 hrs have been utterly problem free until my push rod kludge failed, and with the new welded extension to the push rod, he's back in action with full power again. So the keep to success for a propane CS is a CA110 carburetor, Garrett type regulator, and a hot spark module. A special thank you to Gary at DES again for his awesome technical support on our conversion project.
I'm surprised there isn't a surge of interest in CS's for conversion.