I know this doesnt answer your question but one thing you must consider is how the plane balances. I have a tai ji 60 which I installed a ys 91 into. I still needed 4 oz weight in the nose in order to balance it. with the saito 100 I would have needed 10oz. In this case the ys 91 was the better choice of the 2. From now on I will build my plane and check how much nose weight will be needed. I will order an engine based on what I find.