A Saito 180 is overkill. IMHO, the USL is not a 3D type airplane and doesn't need hover type power. A 120 will give it unlimited vertical so what more power is needed? And... keeping it light is a goal. Someone reported that a Zenoah G-26 magneto combination did not have unlimited vertical and it wasn't obtained until after lightening with a electronic ignition conversion. On the other hand a G20ei is proven to give unlimited vertical so the more powerful G26 magneto can't make up for the increased weight.

Sure, the Saito 180 will work... but think of the clean up and fuel cost compared to a small gasser.