Usually I see rear brake problems on vehicles driven in northern climates where they use lots of road salt. I don't think N.C. gets much snow or uses road salt?
Regardless, rear disc brakes do require more maintenance than the drum style. This is partly due to the fact rear brakes are subjected to a lot more debris... mostly thrown up from the front tires. This debris can become lodged in the moving parts of the brake system and eventually the pads will 'seize' within the calipers causing uneven wear, noise, rotor warping, etc. Note: This problem is not specific to Nissan but to many vehicles with rear disc brakes.
The solution is simple: Disc brakes need to the thoroughly disassembled, cleaned and lubricated on an annual basis, usually in the spring. In northern climates, you may have to do this more frequently, maybe every 6 mos. With proper maintenance, they should last a reasonably long time.
I wrote up a very detailed DIY article on disc brake service. You can find it in the Technical Information Articles section of the forum:
http://www.nicoclub.com/articles.php?id=425794