I have one on my WK2. I can't speak to the JKU-specific mounting, but the rack itself is solid and easy to assemble. The fiddly bit is getting it mounted up straight.
any issues with sealing the 16 holes from water - i see they spec a foam washer surround as the sealing mechanism. wondering about wear or aging of the foam causing an issue.
thanks
i really like these - light, strong, nicely designed
The sealing washers are made from a pretty dense, firm foam, so I imagine they'll hold up for a good while. A dab of RTV would probably take care of it for good.