I'm basically doing my gravel driveway and a few spots out in the yard. When I went to TSC, I asked them what they would recommend. At first it was Amine 400 2,4-D I believe. The next summer it grew back so I went back and was told to try Barrier. I don't recall what it's makeup is but it does say for "up to one year" (duh).
I sprayed it with Amine 400 again last summer because I ran out of Barrier and this is what I have again. I originally told them I wanted to get rid of the weeds, they have been no help yet.