My business used cases of M66 for the same reasons: wholesale/auction work and one-step cars
With a Gem orbital and terry pad, it did OK at putting down some protection and adding to the look just a bit. The inexperienced staff used it on white, beige, silver, and cars that didn't need any rotary work.
With rotary, it'll do fine with one of their W8000 pads. We used wool for the ragged cars. Sure, it left polisher swirls, but the dealers didn't care. I couldn't care for the price. With wool, it would rip through oxidation quickly.
Actually, no matter the application, it's inexpensive, works quickly, and wipes quickly.
It also goes well by hand when polishing spots where a machine won't reach. It's what I use in door jambs as well.