i bought my Jeep used and it overheated after three months. IT WAS NOT THE JEEP. it was negligence. I just got a new motor for it and the reliability before the new engine was unbelievable. at 138,000 miles it didn't miss nor did the tranny slip nor did it burn any other fluids other than gas. Plus for an SUV it got good mileage both for fun and work.
My favorite feature is the upgradeability. You can do anything to a Jeep, cosmetic or performance, and it will always work.