I see lots of recommendations for the Jeep. I own an '88 Cherokee with the 4.0 and a '97 Explorer with the 4.0. Between the two:
Jeep:
Pro: A tank in off road conditions, 4.0/transmission are rugged and durable, a true "utility" in the SUV, parts are easy to come by (lots made... Not sure where the comment on parts being hard to come by came from...), better fuel economy than the explorer!
Cons: Smaller Interior, rougher ride
Explorer: Very comfortable interior, more space, parts are extremely easy to come by, smoother ride (though still a truck)
Cons: Lower ground clearance, engine (4.0 anyways) has lower durability (though nice to drive), 5.0 will be an AWD (no true 4x4 available behind the 5.0)
Between the two, it would depend on what you are going to do: The jeep is the better utility vehicle, the explorer is a better grocery getter/station wagon with limited off road ability.
Not better or worse than each other - just different!