Good, but could be better
We had a 16 ft3 Yakima Rocket Box that was stuffed full on camping trips, and hoped the 21 ft3 Sky Box Pro would make packing easier. Well, I've noticed little difference and had to get a tape measure to make sure we actually got the right box. Perhaps I need to pack more efficiently, or maybe Yakima was a little optimistic on their volume specification. If you're upgrading from a smaller box, measure your current box and compare carefully to the Sky Box Pro so you know exactly how the extra cubic inches are distributed.
The new clamp mechanism is great. It is very easy to attach this box to my factory cross bars, and I no longer need to insert screws from underneath the box while reaching inside the box to secure them...which was painstaking. I also like being able to open the box from either the right or left side, although I don't think the box opens quite as wide as my Rocket Box.
The one-handed closure is convenient, but there's room for improvement. A good amount of force is needed to release the closure. Anyone can do it, but sometimes you wonder if the closure is locked, or if you simply must apply more force. One of the two closures on my box failed so REI is replacing the box. Hopefully, this is an isolated problem.
I also find that it is nearly impossible, or at least, very difficult, to remove the key from the locking core unless the box is locked. This is inconvenient because you don't want your key (or keyring) dangling from the lock whenever the unit is unlocked. I wish you could remove your key, regardless of whether the box is locked or unlocked.
The Sky Box Pro is noticeably more aerodynamic than the Rocket Box. With the Rocket Box, I could "feel" that the box was attached to the vehicle when driving on the highway. However, with the Sky Box Pro attached, it feels the same as if the box is not on the vehicle.
The finish of the Sky Box Pro is smooth and not textured. While the improved aerodynamics do not reduce the number of smashed bugs that cover the face of the box, it does it make it much easier to clean them off without any residue.
Follow-up from 2009
I wanted to follow-up on my Aug 25, 2009 review.
Unfortunately, I rushed into work on a Monday morning, forgot my Sky Box was on top, and destroyed it by driving into a low-clearance garage.
I purchased a new Sky Box Pro 21 in 2012. The new box has some small improvements over the model I purchased in 2009. I noticed immediately that the lid is stiffer. The 2009 lid was fine, but the new lid feels more solid. The closure struts are new. They were formerly plastic hinges which had some play in them, and I could envision where they might bend or break if I improperly packed something too close. The new struts are metal pistons and akin to automobile liftgate supports. This probably contributes to the solid feel of the lid upon opening and closing too. You still must keep the key in the locking core while the box is open, but at least they have a prominent sticker on the box (which is removable) that tells you this. No other changes that I can discren. Still a great box, although I still wish you could remove the key, and that the lid would open a little wider. Also, looks like an expensive box got even more expensive.
By the way, read-on if you want to know what happens when you drive into a low-clearance garage with a box on top. The box cover was not too stiff and it essentially got sheared off/torn. It was like driving into a garage with a very stiff cardboard box affixed to your roof. Whether by design or by luck, because the lid was not too strong, it took the brunt of the damage. The lower tub portion was undamaged. If the lid were stronger, it might have stayed intact and ripped the factory rack off my Ford Expedition. As it was, one of the factory cross bars was ripped-out while the other was simply shoved back in its track. So, in addition to replacing my Sky Box, I also had to replace a factory cross bar. However, that was cheaper than replacing the factory rack, so I count myself somewhat lucky in the face of my massive stupidity.
Lived up to expectations
I ordered this for a 2008 Yukon XL Denali with the factory flushmount side rails and cross-bars. I did fit the box on those rails, but preferred to utilize the Yakima RailGrabbers and round crossbars I already had, it felt sturdier to me than the GMC factory rails.
This box is amazing - it swallows all the gear I had planned on and more!! It was simple to install alone (although heavy and awkward), getting it locked on within 10 minutes at most.
The box rides well on the truck, you hardly know it's there. By looking through the sunroof I can see that empty it bounces some while driving (expected), but when fully loaded I noticed zero movement at highway speeds.
The included cargo mat and bungee are a great touch. Comes with matching lock cores and 2 keys, but of course can be swapped out to match the cores on your other Yakima gear.
Great product, I am looking forward to using it for a long time.
We purchased the new SkyBox Pro 21 in Mar '09. It is the best cargo box we have owned and is outstanding in every respect. Three keys to this cargo box that make it stand out: (1)excellent latch/lock system, (2)ease of installation with quick clamps and (3)durablility. We use it primarily for skiing and have travelled from the Midwest to the West on two occassions with the SkyBox Pro 21. It is aerodynamic and we noticed very little wind noise. Highly recommend.
Quality Rooftop Box
This is a spacious, very easy to install, well-designed rooftop cargo box. It is highly aerodynamic and produces no "wind noise" on the interstate. I have it atop our Suburban and it has negligible effect on the vehicle's driving only noticing it during severe cross wind. The latches that hold the box closed were "sticky" at first but they seem to be unlatching more freely as the box has gotten more use. A wider box this length would be ideal.
Update from previous comments
Although a long wait time (20 min+) the Yakima customer rep knew about the problem and offered to send a replacement part free of charge. He didn't even want the faulty part shipped back. I received the part in four days.So, I had a faulty constructed part but it was quickly replaced at no charge. I've owned my box for a little over two years.Yakima's love it as long as you own it appears to be a truthful statement.
I need to learn how to pack it better and use all the available space without having to dump everything out when I need to find something. Great for camping/traveling with lots of stuff.