I know that member Retrodog likes the B&S "commercial" turf engines, but I am not impressed at all. They are basically the old Intek engine with some fancier and more modern updates to them. B&S is still over rating their engines for HP BTW, so a 30 is more like 26 actual hp. There's a reason that the B&S CT engines cost less.
I have an FX850 currently, and am very happy with it so far. I used to like Kohlers but my last two were such huge P'sOS that I will go out of my way to avoid one if I have a choice of brands on any machine I look at. There are others here who feel the complete opposite of me, like Pro Street Camaro, and that's fine. To each their own. You can only go off your past experiences, and his were different than mine with both Kawi and Kohler.