The latches are awful for such an otherwise rugged system. I bought the Skybox 16S last fall and used it about five times before the latch on the driver's side broke, and I was no longer able to open that side of the box. Like an idiot, I used it 2 or 3 more times, until the passenger side latch also broke - this time with all my stuff inside.
Fortunately I was on my way home instead of trapped on a mountaintop without access to my food or gear. I had to drill out six rivets, rendering the entire box useless, and am awaiting a replacement under Yakima's lifetime warranty. Apparently this was a common problem with Skyboxes manufactured in 2009.
Note: If you buy one of these to take on a ski or camping trip, you'd better keep an axe or maybe a chainsaw in your car to make sure you can get into it.