I had the old York box and used it for a seat in my old frame. The lid didn't like to be sat on for 8 years
, the lid started to warp, and finally got a hairline crack across the middle.
A buddy of mine has the new gray one. It's more rigid, but I still doubt it's 100% waterproof in a flip.
They never were "dry" boxes, but are pretty good "mostly dry" boxes.
The lids aren't rigid enough to be 100% dry with just two straps pulling them closed.
If I wanted to make a York box 99.9% dry, I'd cut a piece of plywood to fit the lid exactly and edge it with some 1" x 1" pine to press down exactly over the closed cell foam gasket. Then strap that over the lid.
They're decent boxes for the money. Two will fit the long way across a 54" wide frame.