I think folks look at the cans side-by-side and figure that the stuff with 'performance enhancer' or 'stop leak' is an upgrade from the plain stuff.

Who wouldn't want 'performance enhancer' for just a little more money, right?

The unfortunate thing is the vicious cycle this sets up in the marketplace. Folks look for a quick-fix-in-a-can because getting their AC serviced is so expensive. All the assorted crap moving about in AC systems is a major cost factor for AC technicians, and the cycle repeats...

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1986 300E 5-Speed 240k mi.