Info on the Ford motorhome chassis can be found at the Ford fleet website.
Here's a direct link to the F53 stuff:
Ford Fleet F53 page
All that's new for 2006 is the powertrain, if everything I'm reading is right. There were significant chassis upgrades for 2004 that carry through of course. My 2004 Adventurer has a 2004 chassis, but they were still building some on 2003 chassis (around Thanksgiving 2003).
I don't have anything to compare it to, and mine is a rare 31Y, so I really can't offer up how it compares to a Workhorse.
Tim.