I've seen some of the minor problems--especially cosmetic ones-- experienced by other Cherokee owners:
1. Drivers seat side vinyl started cracking almost immediately. I've never fixed it.
2. Both front power window retractors failed at about 30,000 miles. I replaced them for about $100 each (I did the labor myself)
3. Oxygen sensor needed replacement at 122,000 miles.
4. Drivers side wheel bearing assembly needed replacement at about 145,000 miles.
5. Fuel pump failed at 156,000 miles.
6. A/C pump clutch failed at 161,000 miles.
Other than that, and an annoying "sticky" lock on the back hatch, this car has been indestructible. All other work has been standard maintenance, although I've never even replaced the shocks since the car doesn't bounce and I have almost 70,000 miles on my current tires.
My XJ has NEVER gone out of alignment, nor has it ever failed to start (except the one time that the fuel pump went bad earlier this year).
This truck is far more solid than any other I've ever had at this mileage. I still drive it every day, and can easily see it going past 200K miles. It goes through plenty of road salt in winter. The underbody is amazingly rust-free thanks to very generous use of galvanized and stainless steel (the exhaust is all-original). I've never driven a car in Michigan winters that stayed this clean underneath. On the down side, there are a few rust spots on the roof (top of the A-pillars and one below the drivers side rear window).
I've always changed the trans fluid, transfer case and differential oil (along with engine oil, of course) according to schedule. This is one of the most overlooked aspects of keeping an old XJ running. These, and good lubrication of the suspension on a regular basis.
I still use my Jeep to tow Ford and Chevy 4x4s out of the snow-- usually because they have crappy OEM tires, but also because of failed electronic 4x4 switchgear. The basic Jeep Command-Trac is a very reliable box.
I find the factory stereo (on the Classic, which has a premium Infinity sound system) still very good after all these years. And interior comfort is fine in the front seat-- less so in the back.
Heat is phenomenal, and I've never had to service the heater core or thermostat. I do hate the HVAC controls, though-- why can't they deliver heat to BOTH my hands and feet without turning the compressor on?!
Although I bought my Jeep Cherokee Classic on a whim back in '98, I'm hooked on this great little truck.