When you decide on an additive to use, google the MSDS for it. Read the list of ingredients, then decide if you REALLY want that stuff going into your engine!
That is, if the MSDS doesn't tell you that the ingredients are "proprietary information, and will ONLY be disclosed to medical professionals"!
It is likely you will find that the additive is 95+% acetone, with a little light machine oil.
When I had an old Dodge CTD, I never used any additives, except once when cold weather caught me with summer fuel in it, and I had to add anti-gel. My son now has the truck, and it is approaching 280,000 miles on the odometer.
Use what you want, they are really pretty much the same stuff when you read the MSDS. I don't believe any additive is necessary.