Hey Matthew,
While I totally agree that the X and S Type have had their fair share of reliability problems, the XJ has had really excellent reliability, and pretty good resale value. According to JD Powers, the Jaguar XJ scores higher than almost every other BMW and Mercedes. So, I agree that the S and X are not high quality Jags, I think the XJ and XK8 are very solid cars, and built really, really well!!