Mine developed a sag after very little use. I seem to recall reading that some have broken. There are a couple of metal stiffeners screwed to the underside but they don't seem to be enough. I got a couple of PVC flanges from the big box store and made a center support using those and a length of 4" PVC that I had in the garage. I only use it while in the "bed" position and made it just a little (1/8" or so) longer than it needed to be thinking that it might remove some of the sag over time. It's nothing fancy and I store it in the outside compartment when it's in "table" mode. To install, I lift the edge of the "bed" and kick the support under. The folded legs and stiffeners keep it trapped in place.
2013 F-350 CC SB 2WD 6.7PS
2013 Eagle Premier 351 RLTS
-SOLD- 2012 X23B
-SOLD- 2003 Ford Expedition 5.4, Bilstein shocks