It of course depends on what type and amount of gear you plan to carry. In general, the roof carrier is very nice to have for road trips because it keeps the inside of the car relatively clear.
I have a '99 EX with factory (aero) cross-bars and use an older-style Yakima Rocket Box.
One issue you'll find with many of the long boxes like this one is that the rear hatch will bump into the box when fully opened. Some boxes may be listed as incompatible with cars because of this. Just a minor inconvenience for me. Not wanting to stress the box, when it is installed, I tie a cord from the hatch inside handle to a screw inside the car, so that stops the hatch from bumping into the box.
I think some of the newer boxes (e.g., the new Yakima RocketBox) are aware of this issue for many minivans and SUVs and the back end of the box now tapers upward to avoid the raised hatchback.
General comments:
Long vs. fat is more aerodynamic for the same volume, although I have not noticed any measurable reduction in gas mileage when the box is installed. The boxes themselves are generally very aerodynamic in shape. A long/narrow box also may keep some bar space available, e.g., for mounting bikes or surfboards, etc.
Be aware of your new vertical clearance requirement. Watch out in parking structures, especially if you let others drive your car.
Make sure you close your box before driving away. I know it sounds silly, but almost everyone leaves it open at least once. If you're driving along and notice strangers staring and waving at you a lot, you may want to check it.
I find it takes about 10 minutes to mount or unmount it from the car. The box mounts are all universal - work on factory aero bars, Thule, or Yakima bars just fine - probably best on aero bars because they're flatter.
They're great for group ski trips - just throw all the skis, boards, and poles up there - no need to clamp them down, etc., and you can fit a ton of stuff in there. Also, when locked and parked, nobody can tell whether there's anything in there worth stealing. (vs. if they're in ski racks)
