Well I know this,

The OS 160 FX with stock muffler and APC 18X6 prop on 5% nitro 18% oil will run for 5 minutes 20 seconds @ 9200 RPM on the test stand. Put a tuned pipe on it and it will again outpull the tuned pipe equiped MVVS. As a matter of fact I suppose you could use the MVVS pipe with a different header.

The MVVS 160 glow no longer comes with the roller bearing rod and I think it needs just as much oil as the OS.

200 grams less? Can you confirm that?

The MVVS engines are very good but the OS 160 FX is the king of the 160's below $275.00.