I just bought this jeep in college with 308k miles on it. I was pretty wary about having problems at that high of a mileage, but so far the only thing that needs replaced is the tires and maybe brakes. I had to test it out in the mud today and the check engine light came on. Great drunk person carriage, I've saved a lot of lives driving people around in this thing. Wouldn't trade it for anything.
4WD & V8
Better fuel pump and cooling system. When driving for long periods of time (i.e. 130+ miles) I could tell the engine was running hot. Most '98 SUV's do though.