Hemi Joel, all shocks are valved based on the expected load and use. You do bring up a good point in that one size doesn't fit all.
My truck is a different brand as well as 17 years newer and different construction. I also have 19.5s all around and run 80lbs in the front. Just because my 4600s are perfect on my F450 doesn't mean they will work for someone else. On one of my trips last summer for an extended trip with all supplies, my combined weight with almost full grey/black tanks and full water was 14,400. I'm assuming that is more than your total weight. Of course, I'm not always that heavy.