Cub Cadets are definitely MTD's top-end offering. But other manufacturers like Husqvarna or John Deere, or Toro/Wheel Horse also offer in
best lawn mowers. "Kohler Engine" doesn't mean much these days anymore. Kohler used two have one line of engine - the flathead K-Series. Then they expanded the lineup to their OHV Command series - also a very excellent engine. But Command engines were expensive, and mower manufacturers wanted the Kohler name, so they added the low-end cheap and cheesy Courage series that did a ton of reputation damage to the brand.
But money talks, and they've continued doing that even further now. Kohler has many different engine lines to suit just about every possible price point these days. They're all pretty much junk except for their "premium" Command Pro brand.
Basically, unless it's a Command Pro Kohler engine, it's not going to be any better than a Briggs and Stratton or even a chinese clone v-twin.