I saw quite a few Evolution .46's run like clocks, so I didn't hesitate to buy an Evolution 1.00 NX to power my Vectorflight Edge 540.......since March, I've been battling with this engine, and I'm not happy. I have literally tried every setting on both the low end and high speed needle valves, and every combination of both. I've tried different fuels, different plugs, moved the fuel tank, checked the lines.....EVERYTHING! The engine has a ton of power, but I can't keep it running.....it either leans out or is too rich during transition....and that happens within a tiny turn of the low-end needle valve. Just when I think I have it running pretty well, I'll take the plane up, but every flight I've had on the plane, except for one, resulted in a dead stick. One landing caused damage to the plane. I've decided to cut my losses before I destroy a great flying plane. I'm currently looking for a new engine for the plane, and I'm planning on sending the 1.00NX to Horizon.