Owned a 2005 Pathfinder SE Off-road from 2005-2008 (totalled by dear impact)
Currently own a 2008 Explorer Limited
since both vehicles fall within the same model designs i think i might have some valuable input. (05+ pathy 06+ explorer)
Pathfinder was reliable. put 47k miles on it with minimal trouble. Engine and drivetrain are solid. 4.0 was quick and liked to rev. it rode like a truck, and the engine is a bit rough and noisy. (but like i said Quick!)
black interior scratched kind of easy and felt hard. bose sound system was much better than the ford audiophile. pahfinder was better off-road (i had off-road package and no auto 4x4 just 2wd, 4wd, low in my opinion though it was not as good in snow and rain as the explorer. always wanted to plow. (even after replacing tires with bridgestone REVOs).
held it's value pretty well as insurance settled with me for 18k (3 years old and 47k miles).
Explorer: I have a v8 AWD. rides like a luxary sedan. smooth and quiet. lower feel and more solid on the highway. the pathfinder v6 was quick, the v8 in the explorer has nice torque but definitly not as rev-happy as the nissan v6. features are very similar and interior is layed out about the same. less rattles in the explorer. my nissan was plagued with rattles both inside and out. feels very solid in rain and snow and at higher speeds. havent and dont plan to take it off-road. but the pathy definitely would have the nod there. back seat is more comfortable in the explorer (2nd and 3rd rows).
we have owned numerous explorers from all generations (93, 96, 01, 03, 08) and this was my first pathy but the family has owned nissans from 00, 04, 05, 08) you won't be disappointed with either choice, and unless you get a lemon, either will be a reliable sturdy vehicle.
couple of other notes
05 was the first year of that generation pathfinder, there are some known quirks that you may want to look into (TSBs) idler pully i believe, rust on rear gate, rear springs, trailer wiring...
06 was the first year of that generation explorer. the interior door handles are a huge pain on the 06, 07+ were better. v8 6spd auto needs a software update on some 06 v8s to fix a hard shift to first upon stopping.