The car analogy is correct. Both horses and mules are like cars. If you buy a new "car", you send it off to the "custom" shop and then you have to use it. If you don't drive your car much the seals become dry, the gas goes bad, and the car won't do what you want it to.
If you buy a used car, the owner always says how great a "car" it is and skips over the problems. When you start driving the "car" you notice it pulls hard to the right, will not get over 35 mph, the steering is very sloppy, or the brakes seem "soft" quite often.
The "car" never gets the mpg advertised. When we are learning to drive, a 4 cylinder seems mighty stout, until you get the hang of driving, then you want a v8. Heck I even bought a v10. Some "cars" come with lots of chrome (which tends to rust), while other cars are kind of plain-jane, but run forever.
Many "cars" have to go to the shop often, but expensive "cars" seem to make their owners feel they have to go to the dealership to receive service. The issue of tires is always present, as we must buy new tires quite often, and rotate them even more so.
Some "cars" have cruise control, while others have to be white-knuckled to whole time you are in the seat. Some cars couldn't drive up a 7 degree grade and stall, then falter backwards, even though they seemed to have plenty of power in the flats.
If you are not a "mule-guy", then buy horses. It is hard to beat a great mule, the problem is finding one. I broke horses, then I went through my mule phase. Now I am back to horses, so that is what I prefer. Horses are more forgiving. They make fine pasture ornaments.
"You ain't never been kicked, 'til you been kicked by a mule."
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