I don't know how you quantify what that stuff does. I put in my 454 I had, but honestly, couldn't tell you if it helped or not. I run Mobil 1 10w30 in my 8.1 and ran it in the other 8.1 I had. It flows quicker at lower temps than convential oils, and has a higher boiling point. So, if I ever get into extremes with it, I should be covered. I change it every 6,000 miles. I think you can go 15,000 miles on it with a filter change in the middle. I wouldn't run it that long, but I don't have a problem with 6,000. It should easily protect it that long. I have seen some amazing mileages out of gas engines with Synthetic oils.
I took a Mechanical Engineering class in college, we called it Putt Putt 1. The professor said one thing that I remember in those hangover ridden days. Don't put a bunch of additives in an engine. All they need is good maintinance and good lubricants and they should do just fine. He said when you start mixing those additives, you are asking for more headaches than you already have, and you spend a lot of money doing it.
Like I said, I tried it on one of my trucks, and couldn't really tell if it made a difference. At $40/bottle, I sure wanted it to make a difference.