I had a 22Kw Generac installed when we build our house 6 years ago this month. It runs on natural gas and like all generators I guess, tests itself at prescribed times. Oher than the testing, ours hasn't run for 3 hours over that period of time and we've had no issues with it. I suppose the Kohler is likely rated higher, as is the Cummins. You're buying peace of mind.
