Thanks for the response. I didn't get any model numbers on the Kawasakis, but I'm looking at residential mowers, not commercial. The engines are on similar Kubotas and Gravelys, and are in the 20-25hp range. I've narrowed my selection down to 2 mowers of mostly equal qualities, but one has a Kohler and the other a Kawasaki. I favor the Gravely ZTXL48 and it has a Kohler. A friend expressed misgivings about Kohlers so I wanted to check with other users/mechanics about the 2 engines. So far I have found testimony for both engine manufactures. It appears that owner care may be the determining factor in engine performance and longevity.