Deb here: I have driven duallys and hate them. And it's not that I can't handle "size" because I drive our 28' Class C all over - BUT: the Class C is an RV. I expect to park it and use a toad. Whatever is towing the 5er is also a "car"; and after using our F-350 SRW as a "car" for a few weeks and discovering what a PITA it can be to park - I can't imagine dealing with a dually.
Granted, if we wanted a much larger trailer, then I'd simply deal with the dually needed to pull it. But if there was an option for a SRW, I'd sure go for that first.
(Sarcasm coming) And since MY husband seems to LIKE having me along and sharing the driving and set-up duties; and feeding him; doing the laundry and housework and making his life generally better for the last umpteen years.... he asks for, and respects, my opinions ;-)