The OS are far more efficient than the Saito. Not Knocking the Saito (I like and own those too) but the OS is the best running engine I own. 1800 idle and instant throttle response to 8500 on a Mejzlik 18x8. My Creek Extra is a rocket vertical. This combo pulls my friend's World 80" Extra unlimited but slower. The numbers are probably closer to a 15-20 oz difference from the ZDZ also. I have to concede though, the ZDZ is pretty light for a gasser.