While touring with a band in Korea, I had plenty of time to dream about a new car for my return to the states. After finding that the XJ8 models were very unreliable for the first few model years (and the newer ones are outside of my price range), I chose the 97 XJ6 over any other model. I "test drove" it after I bought it, driving it from NJ to FL, over 17 hours of driving. It presented no complaints.
Since that long haul, I have driven it across Florida, I am on the highway all day for business, and often pull off violent maneuvers in day to day traffic. The car doesn't seem to mind.
I was so worried about the absurd amount of miles with which I was burdening the Jaguar, even though it had zero mechanical issues, that I bought a Jeep as a daily driver. After a month, the Jeep sits. I just can't bring myself to drive it when the Jaguar is in the driveway.
From the feedback I get from observers, it is usually "You must be getting paid too much!" or "You drive a JAGUAR??? I have ALWAYS wanted one, but I could never afford one." The most common comment is "Wow, those things are so unreliable! (insert words of worried advice) " These are comments from Mercedes and BMW owners, doctors, lawyers, and the rest. Everyone loves this car. This one in particular is painted to resemble the XJR model, which looks far more modern.
The authorities even treat one differently in a Jag. I got pulled over with a suspended license from failing to pay a violation, and the cop said, "I'm really sorry to inconvenience you, but I just wanted to let you know that your license is technically suspended, and I know those guys sometimes mess up, so just check it out when you have an opportunity." This sort of encounter has happened several times with the police.
Drive it. Enjoy it. Love it. If you destroy it, buy another one. You could buy four of them for the price of a new Camry or Accord.
The XJ6 is the best kept secret in the used luxury market. Beware the early XJ8s.