I researched this awhile back, and found an interesting article that actually did viscocity testing on different additives, 2 stroke oil in the fuel ranked very low for lubrication, actually worse then no additive at all if I remember right.
We use to run power service on our fleet of cummins back when I was doing construction, probably ran those trucks a combined 400k miles and never had a pump failure. thats what goes into my powerstroke now, though im sure there is better, ps is found very easily and not to expensive.