In an earlier thread about towed graders, I mentioned that Adams County in WA had some in use about 2002, (when I saw them last.) They were towed behind an F350 with some weight for traction, they were on rubber and moved along right smartly. I asked why the tow behind, and was told they were cheaper and faster than a normal grader when it came to profiling ditches and shoulders. When moving from site to site, they moved about 60 mph. Two people, a truck and tow behind grader could (according them) do about 4 times the work that a normal grader could do.