Gerry, we're good. No offense. I know it is one of those things, like motor oil, car manufacturer or politics that can send people sideways real quick like. I offer my opinion and let it go at that. I enjoy the information from this site and don't want to loose that from being a richard-head.
I don't lug my tractor, I use the power that is needed for the job. Being what it is, I feel using just slightly under WOT is better and has not hurt the engine in any way. I won't say I'm an expert, but with my 23 yrs of drag racing, building engines, trans, rearends, welding, machining background I think I have not done anything wrong.
I wiggled the balance gears. They are not tight fitted. The shaft they ride has oil clearance, you can just wiggle the gears. The teeth themselves look fine, no sharp edges. The inside of the engine is spotless. Like I said, it runs perfect, never used a drop of oil since I bought it. It does have a slight "noise", which I'm guessing is the balance gears "rattling"? It is not a rod knock, it has been there since day one and why I get edgy about running it hard.
As for mower deck noise. I agree, some have inherent noises, more like wind noise from the blades. I'm sure there are all kinds of designs out there. I was just flabbergasted how dead quiet this 42" deck is with all new parts in it. You can not tell it is running, and after the last 10 yrs of it howling it will be a PLEASURE to mow.