You're still better off with a new set of injectors. They do wear out over time.Exactly. This is why I never go on things like fuel economy numbers, unless somebody can back it up with solid testing and proof.
Hotshots (the oil additive, not their fuel additive) is the one product where I have seen multiple people looking at injector replacements try it and come out with extremely good results.
This snake oil is just a temporary fix at best.