I have both, most of my 2 strokes are converted to diesel since I fly sport and scale both the 2 strk diesels and the 4 strks are
propped to turn approx 8000 to about 9500 which make them pretty quiet I have had no problems with the 4 strokes, and they
run as reliable as my diesels 30 thru 1,2 on the 4 strokes and thru 90 on the 2 strokes < My latest 4 strk a neat little enya 40 open
rocker I like the sound will have to find a plane for it martin