I like to keep things dry in my bed when not towing and having my tonneau unrolled. I can remember to open and close my OEM tailgate so I can keep things dry. Don't want a 5'th wheel tailgate at any price or configuration.
My 2 cents.
2006 GMC 2500HD CCSB 4x4 Duramax/Allison, Titan 52 gallon fuel tank, Prodigy Controller, B&W Companion Hitch
2010 Jayco Designer 35RLTS, Cummins/Onan RV QG 5500 EVAP, Progressive Industries EMS-PT50C, TST Systems 507 TPMS, RV Flex Armor Roof