Our last truck was not a dually but it was a mega cab.
It was a great truck. We never had any issues with pulling our 40' bunk house.
We did have the slider hitch but never used it, could almost do a complete 90 when turning.
Towed with it for 2 years and never had an issue with bed size
I haven't figured out how to upload photos with the new format yet.
But there are plenty of people on here that I have seen using the dually with the mega and love it. We are going back to the mega again on our next truck. We miss it.