Aw, you guys don't know nuttin' about engines!
Hands down, the very best engines are GMS!
OK, well, I have a couple of these (a 32 on an LT-25 and a 76 on a 4*60) and they've been OK so far but I guess some have had problems.
This is kind of like the Chevy vs Ford arguement (maybe OS = BMW...)
I have an Evo 46NT on an LT-40 that's worked well...
Maybe someday when I build my "dream" RC plane, I'll spring for an OS 4-stroke.
Until then, I'll just fly cheap planes with cheap engines.
Dave
AMA 847123