Do fuel injector cleaners work? on 1991 Pontiac Bonneville

I have pros & cons. Iwas told by one mechanic that as a whole cleaners may do more harm than good. He made one exception for any brand that contained a particular additive, which i don't recall.

Asked by for the 1991 Pontiac Bonneville
Some do, some do not. At the shop I used to work at, and in all of my personal vehicles, we used B&G 44K it is kind of hard to find, and is very expensive ($30+ a can) compared to others out there, but we have always had good luck with it.

However, it is very agressive and strong, so we always told folks to put it in at the gas station before you fuel up. Top off the tank, and only drive it down to 1/2 a tank, then refuel completely.
Please note, I am NOT in any way shape or form associated with B&G or any of their subsidaries or blah blah blah. I am just a tech that likes a particular product and am passing word of mouth here...
This is the injector cleaner additive i was trying to recall. Appreciate your assistance