I agree, just go with Sears Craftsman. I've had mine for years, and she still cranks up, right away. If you're going with self propelled, be sure to get large rear tires with the front wheel drive. They are much easier to turn, than rear wheel drive....
www.mow.com this will help you out with your diagram
The kohler always had a very good reputation. Check consumer reports for what they say.