Unless you are truly working the tractor to its limits, I do not believe you would notice a difference in power, between the brands. Honda and Vanguard are produced oversees, believe Kohler is still built here - but not sure. Your decision should also include 'Kit' vs 'No Kit'. If you intend to purchase a kit, I would give as much consideration to the quality (or lack thereof) of the kit, as I would about the brand of motor. I re-powered with a Honda, and while I love the motor, the kit and customer service, was nothing short of a complete debacle. If I had it to do over again, and based on comments in this site, I would buy kit from Jim's Small Engine - he uses Vanguard.