Was it glassed and painted on the outside and, at least, epoxy coated on the inside? You should be able to expect it to last almost as long as the boat if built properly.
How much weight can it handle? Considerably more than the sturdy (as far aluminum boxes go) .090in wall thickness aluminum boxes I built.
Jake,
I don't know much about it since I inherited the box from the boat's previous owner. I know it was huge, wood, painted and thats about it.
Now that I've got some creative juices flowing, I'm feeling like putting together a box using all that 2" structural foam I've got in the garage. Kate would kill me.