In high school/college I worked for a large farmer, one of my jobs during the summer when we weren't in the fields was to mow around the outbuildings/grain bins at the various farms. He had a 60" Grasshopper. That was a mowing machine. Put a lot of hours on it, I ran it for 8 years, and not sure how old it was when I started, and it never had an issue that I didn't cause due to improper care.
Dad got sick of the Craftsman lawn tractors and their wearing out every couple years and bought a Marty-J by Deines.
Its a commercial duty mower, built for using repair parts rather than throwing away the thing, bearings rather than bushings, etc. When I was a kid it took me 4 hours to mow the yard with the 32" Snapper. With this he can have it done in just over an hour, and he mows quite a bit more ground now than I did then. He could buy a pair of Craftsman tractors for what he paid for the Marty-J used, but it is still going strong and will continue to.