Do The STP Super Concentrated Fuel Injector Cleaners Actually Work?

We just purchased a 2012 Hyundai Sonata GLS with 40,000 kms on it and it feels like it is running a bit rough. I am considering trying the STP® Super Concentrated Fuel Injector Cleaner to see if it will help alleviate the problem.

Has anyone tried this product? If so, how well did it work for you?
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