Cannon Fodder and EQ1, I have not seen except for pictures, any of these engines, nor have I talked to anyone who has them. They sent me a gas engine to evaluate and it did not go well. I think UMS was put off with my candid responses. Threaded heads onto cylinders is a high precision process that requires top notch machining. Personally all my engines had no issues but I had acquaintances that had great trouble especially with the 160 gas. -Tom