Guy's:
I have used Stanadyne in my 08' since the first tank emptied. It is the #1 fuel additive in the nation. It is produced by an INJECTOR Company, they should know what works if anyone would. The difference between the regular and the JR. is that the JR has NO cold weather properties etc. that's why it is cheaper to buy.
I just went to my local Diesel Garage and ordered a case(6) of the 1/2 GAL. of Stanadyne. It will be $18 a jug X 6 jugs, plus tax. ($108+6%) One 64 oz. jug does 250 gal. That's the cheapest I've found yet. You can find it cheap on Ebay, but the shipping kills you. Besides I like to support local businesses.
Just my feelings concerning additives, my Bro in law uses Lucas additive, but that is a lubricant not a fuel suppliment.