Question: Any concerns with water (rain/washing) under the mat?
In 8 years I’ve had my mat out exactly once to wash out from under it. And that was only because a quart of bar oil tipped over and ran under it. There are a couple of drain holes in the front corners so just keep those cleaned out.
My only beef with these beds are the lack of tie down points in the front corners. There are kits available to add them and I keep saying I need to do it, but after 150k miles, you know. You’d think enough people would want them they could throw $20 worth of parts at it before it rolled off the line.