I would say the seal placement is key and even then I would call it more water-resistant. I don't think rain even when driving will penetrate much but powerwashing would, in my opinion. I thought the hardware wasn't adequate when I first saw it but after installing and seeing what the hardware...
My guess it that it involves new TPMS sensors in the wheels. I think the ones we have require the wheels to turn a while before the sensor picks up the pressure. Either they have more sensors on around the wheels or different sensors on the valves in order to instantly sense the pressure...
Interesting that it was a feature touted for the Gladiator Rubicons when announced but "no way" to retrofit??? There is most likely a way but not a cost-effective way for FCA. It isn't that big of a deal to air down and up the way I've been doing it, just a feature that was implied but not...
I like the Decked but still not sure it is the best answer. Since you can reach most of the bed from the side and back, it might be ok to only have the Upper Decker as long as you can secure the payload in the bed so it doesn't move around on you.
I have the Decked System & Upper Decker hard cover installed. Will be at Motor Inn on Monday afternoon if you want to see in person @spenchey . You can read more on my build page on the forum.
Yesterday I installed (almost completely) the Ace Engineering Upper Decker. Since I was doing it myself, I used the ratchet straps to my garage ceiling to raise & lower. Worked great!
I first had to remove most of the Decked System. If you are getting both, I would still suggest fully...