Any good?
 

Stanadyne Performance Formula One Shot?

Looks like a decent product to me. Here's the details:
http://www.thoroughbreddiesel.com/st...ce-formula.htm

As for price point, it looks like Stanadyne is the the most expensive product of the few I looked up. I'd recommend you find out what it is you intend to gain by using an additive and look for something that fits the bill. Obviously an additive strictly for anti-gelling will provide more protection than an all-in-one product. Also, do not use an emulsifier (where it causes the water to be dissolved in the diesel better) as that is prohibited by the book on 2011-2017 6.7L diesels. Instead, look for a demulsifier (forces the water out of the diesel to be filtered by the water separator better).

Stanadyne = ~$0.12 / gallon
Optilube XPD = ~$0.10 / gallon
Ford PM-22-A = ~$0.08 / gallon