I've heard good things about the Magnum and TT 4 strokes. I bought a well used Magnum .81 a few weeks ago, but haven't had a chance to start it up. My understanding is that Magnum, TT and OS are generally heavier than Saito. Saitos are not usually any more expensive than OS 4 strokes. I have a Saito .91 which I am very pleased with. If I could afford it, I would have a 4 stroke in all my planes. They sound great!

-Scott