Cost is always a factor. I like this Walmart price of $10. I add about 2 ounces per fill up of about 25 gallons.
Not a strong dose at all.
Add tax, say 7%.
$10.70/16 doses/25 gallons/17.4 MPG.
That's .15 cents per mile. Not 15 CPM. .15 CPM.
So basically, at the dose I add, if I gain ANY...