We have an '09 with HD tow package, 4x4. We just got back from our maiden voyage with a KZ Sportsman 301 bunkhouse (32') hitch to bumper. We pulled from west of Chicago to St. Joseph, Mi. With absolutely NO issues. We pack light, no water and have an equalizer hitch. The camper dry weight is about 6,400# and grosses at 8,000#, no I have not gone to a scale yet.
I would not hesitate to move on the Expy, it is a great tow vehicle. We have three small kids and my wife and I are not large people. At the risk of getting flamed, we do not all need a one ton dually. Good luck with your decision.