I'm not sure why we seem to have a OS-Saito pissing contest here. I have no experience with the OS 1.60, but from the specs and what I have read it is a fine and powerful engine. But you are comparing apples and oranges. One is a two stroke the other a four. It all depends on what you are looking for. The man just wanted Saito performance comments. You gave the impression the the 1.80 is not up to the task. I am sure dozens on this board can attest to the fact that the 1.80 is an awesome performer on this plane. In addition, with the Saito 1.80 in mine, battery just behind the tank, it weighed 11.7 pounds and balanced perfectly with no additional weight.