I have to agree with Bob on the 2 stroke reliability factor.
I also grew up riding 2 strokes in the California desert as a kid.
We had a saying, " 2 strokes run the best, 15 seconds before they seize up"
I had first hand experience with that saying many times.
The newer Solo and Rotax engines seem to be much better, but every time I see a 2 stroke motorglider take off, I watch it, to see what might happen.
Nick
T