My single courage engine with about 400 hours is reliable. BUT!!!
These have a pressure lubed engine, not splash. And a tiny oil pump so it will take a long time to fill the oil filter. Too long. I have not seen a shop that will prefill, takes them too much time. so evenutally BOOM. As it says in the manual, you must prefill the vertical oil filter. Kohler recommended oil filter now has a drain back valve. To prefill need to use a toothpick or small screwdriver to push back one area of the drain back so it can vent air. Then prefill, and remove toothpick. It does not damage the drain back, but if it did, the original filter did not have one so no bother. I use 10W30 auto oil. stays clean a long time. I have a small yard now, so I only change once every 2 years.
Other than that, no issues. The mtd muffler had issues but removing the screws that hold it in and welding on studs fixed that. Really loud when the muffler falls off.
Rod