Every time one of these fuel additive comparision threads pop up I feel compelled to respond, so here goes.
When looking at a fuel additive one must look at the whole package, not just lubricity. For instance a bio blend is probably the best lubricity improver out there, but what does it do for cetane? Bio actually has less power per gallon than reg diesel. Bio actually has more of a problem drawing moisture than reg diesel, so you would have to add a demulsifier. It also does nothing to stabilize fuel.
I am not calling out bio blends, just using it for argument sake since that lubricity study has been mentioned already, but the same can be said for 2 stroke oil also.
When selecting a diesel fuel additive everything I have mentioned above must be taken into consideration. Do you really "need" the best lubricity improver?, or would a correct balance of lubricity,cetane improver, water demulsifier, and fuel stabilizer suit your fuel system better in the long run?