I can't say how it would work for stunt because I've only ever run mine on a test stand but it's a surprising engine. Just for laughs I ran it once on a back to back experiment against an Enya 60-IIIB. Using a 12x5 prop the Enya made 9,300 revs and the ST made 10,500 while with a 13x6 prop the Enya made 8,600 and the ST made 9,100. Admittedly the ST carb had 33% more venturi area but even so I was quite surprised by its grunt.