Hi Bushie, I may be able to contribute to some of these points, but others, not. First, I agree that Honda mowers are over-priced, and have the impression that they are losing market share among the contractors. Second, some of the chondas are just about as good as real Hondas except for a few minor weaknesses. However if you are not sufficiently mechanically inclined to address those weaknesses you might end up joining the long line of people who throw them away at an early stage. Also, I suspect the chonda you have described as 6.5 hp may not be: the chondas I have heard of that were marked 6.5 were copies of the GXV160, which Honda advertises as 5.5 hp. Third, everything I have heard about the Briggs 850 I/C has been positive at this stage. Third, Kohler engines have never been popular in Australia, and there may be relatively inferior availability of parts and repair expertise, as well as resale value.
Remember that the cable control on modern mower engines (not trimmer or chainsaw engines) is not a throttle control, it is an adjustment of the engine's governor setting, within the governed range. Most people, especially contractors, leave them set on maximum except perhaps when they are emptying the catcher. As far as I know mower manufacturers usually recommend this, because it gives a better lawn finish, better pick-up of cut grass, and better performance when you pass through a slightly longer section of the grass. Fitting a speed control cable to a Honda or Briggs engine does not involve any engine modification, and does not involve going anywhere near the carburetor. Interfering with the carburetor is a very bad idea, and not only because it would void the warranty.
