ALWAYS remember, its not just what the "rated" towing poundage is.........I shake my head at people towing a monsterous trailer with a weenie mid sized toyota truck, Ford Explorer, or Chevy S10.......
Can you say Tail wagging the dog?
While the duallyies ARE more stable for all out towing, egads they're wide and a pain to park....with proper suspension (air bags and Rancho 9 way click adjust dampning shocks) all but the biggest trailers can still be towed with a standard 3/4 or 1 ton truck.
Check out:
http://www.dodgetrucks.org/ for more detailed general towing info comparing many types of trucks. Good forum board.