I am on my second dually and have had dually pickups now for about 10 years. My truck previous to my 2003 F-350 dually was a F-250 Supercab 4x4 SRW 7.3L. I upgraded to the F-350 because I truly felt that the F-250 wasn't up to the task of pulling our 30' Citation 4 season fifth wheel both in braking and handling. I remember the back tires on that truck being so hot when pulling that you could not hold your hand on them and they wore like crazy. The F-350 was like night and day in braking and handling; the rear tires were only warm and that was at 65 psi vs. 80 psi in the SRW truck. I now have the Ram in my signature and it is light years ahead of the F-350. And we have upgraded our fifth wheel to a 36' triple slide 4 season unit which weighs much more than our last trailer and the Ram handles it better than the F-350 handled our 30'.
I will not have a SRW truck again as long as we are towing a large fifth wheel. And the comments about buying 6 tires instead of 4 is a bit skewed too; when towing heavy, the rear tires on a SRW truck wear twice as fast as those on the rear of a dually so the tire issue is not as big as you may think.
My dually is not a DD but I do take it all over the city and parking is not a problem if you park a bit further out and back in. We like the extra exercise so it isn't an issue for us.