I have been using the Pelican Cargo Case BX140R with roof rack mounting system for a few months and want to share my thoughts to those considering this case. (yes I mistyped the model number in the title, but now can't edit it). I've been on a 1400 mile road trip with it, taken it camping, and moved it on, off, in and out of the rig several times. Here are my thoughts:

Overall:
Pro's: Durable, water/wind proof, quick to get on/off the vehicle, great extra space. You CAN get it on/off with just one person.
Con's: Cumbersome to handle without two people, latches that attach the case to the roof mount have very small holes for locks. The locks that fit these holes will only delay theft, not prevent a serious attempt. Price. It did not fit in my garage while mounted to my rack. Admittedly, I have an older house and new houses have taller garage doors. Finally, it does not fit flat on the floor of the 4Runner cargo area (I know not typically how you'd haul it).

Durability:
I've taken this on a 1400 mile road trip through rain and on the beach. No issues with rain or dust penetration. This case appears to be built to the level that one would expect from Pelican, and for the price.

Size:
The box is about four cubic feet. You can lift it yourself, but the reach is awkward, especially when fully loaded. It's nearly twice as big as the next largest roof mount Pelican cargo case - the BX90R. On the other hand it's not as big as a Yakima or Thule roof top case, although much easier to get on/off. The size is great for the bulky light weight camping equipment - sleeping bags, pillows, etc. Generally I also have my recovery gear in here as well.

Mounting/dismounting
I purchased the Front Runner mount to attached to my Rago cross bar system. I had to do some slight filing of two holes to make them work, but overall not a big issue. Once I had the Front Runner mount attached getting the case latched in is a breeze. This is truly a great system. The ads say you get get it from latched to off the vehicle in 14 seconds and they are just about right. I didn't do any time trials, but it's close. On the down side, as mentioned above getting the case up above your head, while fully loaded and not hitting your car takes some work but is possible. With two people, it's not a problem. The other note is that while the case itself can fit reasonably strong/thick padlocks, the latches that connect the case to the mount have tiny little holes that basically only fit a tiny TSA cable lock. This is an area for improvement, but I still generally felt safe leaving it up there unattended.

In total, I like the case and the mount. I bought it primarily for camping and it does the job well. I would also strongly consider the BX90R, but then again 2.5 cubic feet isn't the same as 4.

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