Keep in mind that trick is to keep them clean and the ONLY legit way to do that is to use a gasoline that has a top shelf additive package in it.
The thinking of cleaning is backwards, the thought should be keep them clean.
Top Tier gasolines have very sophisticated additive packages in them, and they work.
By the way, said additive packages are added in at the bulk storage marketing terminal.
They are not a result of the refinement process.
They are a chemical brew that is added after the gasoline has left the refinery compound area and gone to the storage area.
Off brand gasolines historically always got a minimalist package, and I'm pretty sure that's the case to this day.
However, today's minimalist packages are way better than they used to be, and the driving force is the required ongoing injector and valve cleanliness as part of a car's ability to maintain the legislated allowable emissions.
Short story, buy good gasoline and drive to keep your injectors clean.