There's really little new in the world of herbicides. Chemists just seem to twist different chains around to make a herbicide of a different configuration but in the same family. Kinda like when your father is your cousins uncle's best friend and grandfather. It's still the Hatfields. And it's still the McCoys. Get a different name, another patent and a way to compete with the rest of the family.
Grazon contains 2,4-d and a twist on what's know as triclopyr. The combination of the two seem to work to kill tough broadleaf weeds and brush better than either alone. Grazon's big claim is that it's safe to use on pastures where horses graze! Grazon's brother, Crossbow, well, the name would seem to make it sound as though one were there to shoot the horses. After you get either one out of the jug it's hard to tell the difference.