Neither had I, but it really seemed to prevent rail wear (at least there was no rubbing off the finish on the rails) and it really slicks up the rails. I think I read that you should use a good bead of grease, which I did. The gun will hold the grease it needs, which turned out to be true; I only had to wipe a bit off the end of the gun after reassembly, and I never had splatter or leakage or anything else.
I like the convience of the tetra applicator at the end of the tube.
I like the convience of the tetra applicator at the end of the tube.