While looking at the Dandy rebuild pictures I notice that the bed boxes look a bit flimsy with only a .25 inch board and how are they fitted to the frame as that does not look very substantial. I find it hard to believe that 2 people are going to sleep on that if they are over 10 stone each. As my wife and I are not that slim I would be concerned to even have one person sleeping on each bed.I hope the Destiny and Dimension are more substantial as they come out the front and back rather than the sides. They remind me of the Bonair trailer tent we had back in the 80's which had a rising roof and sliding beds and slept 8 but weighed over a ton.
No need to worry they are attached to the dandy with lengths of hd piano hinge and then on the early ones supported by metal legs to the floor,not sure about the later destiny's think they may have an angle support that goes back to the trailer body.
The system has been well tested over the years and is very sturdy,even if the energy is there for a little
,then you have to consider the pvc roof the way it fixes all so adds strength to the bed support,in fact on the four and five berth models you can erect it then put the legs up and move the complete unit round,one dandy owner even towed his across the site like this.