hello Bob: for sure, comparing two mowers is not some sort of statistical analysis, more of the "testimonial" variety.
Can't do a meta or Chi square on that one, that is for sure.
But for my gasoline things, i do use synthetics, i am pretty compulsive about my oiling.
I got to thinking about some of the comments about the Briggs and Stratton warning to use non detergent
oil when i was out cruisin' in the Great Stroker this afternoon. My hunch is that they know most folks never change their mower
oil, and since these small engines don't have filters, they will last longer if the combustion debris and wear particles settle out and just stay down and out of circulation. Just a guess.
I can recall in years past seeing auto engines that ran non detergent
oil (i presume), and when the valve covers were pulled, all you could see was a big gooey blob where the valve train should have been. Interesting happenings in oil, the Toyota oiling problems, the earlier issues with excessive viscosity ratings ( the 5-40 and such spreads), the Syntec suit by Mobile One, and on and on.
I seek pefection in my cars, it is a curse. I have also an addiction to continual modification of otherwise complete and fine automobiles. I just put a $80 Canton Mecca full flow oil filter cannister on my wife's new Jeep Liberty.
All the best,