The larger the engine, the better the sound, in my opinion anyway. I've got a couple of Saito .91's and a Saito 1.00. They all sound pretty much alike. I also have an O.S. 1.20 Surpass, non-pumped, which sounds awesome. I don't know if it is the brand, or the size that makes such the difference, but it is by far the best sounding four banger I've got. It runs pretty darn good too! I'm pretty much a Saito nut, but my O.S. 1.20 definately sounds th best out of all my four strokes.

John