2015 Silverado double cab with 6.5′ box. Need the box length for “stuff”. Just hit 96,000. No major issues. I will most likely always have a double cab (not crew cab, kids are gone) so my dog has a nice place to ride. He earns his keep and would never put him in the topper covered box in a kennel.
found it annoying to have to climb into the bed in order to add or get stuff out of the bed by the cab. No easy way to access that space
They make cargo hooks to get to stuff. I made my own plus the side windows on the topper help get to stuff.