I've recently returned from overseas, and wanted an interesting sedan for my gentle 20 km round-trip commute, but didn't want to spend a fortune.
I found this car for sale in Queensland with just 66K km from new, an elderly owner retiring from driving and in beautiful condition. I had the car inspected and a very thorough service performed. They also fitted a mono-strut in the rear suspension to tighten it up a little a-la-XJR - the ride is still superb though. The car was then shipped across the Nullabor to Perth where I've now been using it very happily for the last couple of months.
I'm seriously impressed by the smooth ride, effortless performance (it's not fast, but it's not supposed to be - "rapid" and "unstressed" are better words and if you press the "Sport" button it will spin to the red line with a very satisfying but civilised growl), quietness and general quality feel.
It also looks superb in Carnival red with leather Oatmeal and Antelope interior. It's a very late (Aug 1997 build) X300, which has a high spec - although not the Sovereign model, it has fully powered front seats, sunroof, CD stacker etc. - and crucially since I have 3 kids, three lap-sash seat belts across the rear seat.
The interior space of my standard wheelbase model is not generous for a car this size, but we have a people-mover for when we need a load of room.
The only niggle for me (I'm fairly tall) is that the seat belt upper mounting could do with going a couple of cm higher up the track, but I find the seat very comfortable, and I can achieve an excellent driving position. The boot is actually larger than I thought it would be (the space-saver spare helps), and if you pack it carefully with different sized bags, it will hold a surprising amount of stuff. My friends and family can't believe what good value it was, or that it is over 12 years old.
I love the slightly old-fashioned feel of the car, mated to a reasonable level of modern safety technology. I really wanted the last of the straight six cars rather than a V8 for exactly this reason. The V8 in my 1967 Maserati Quattroporte was pretty special, but for some reason I keep returning to a straight six - all my favourite cars over the years have been straight sixes.
Even though I drive fairly sedately, I am only getting about 15.5L/100Km (about 18.2 mpg) which is pretty ordinary, but even a short open road run sees this improve to about 12.5 without trying hard. Still, that's at least 50% better than the Quattroporte!
Overall I'm very happy indeed. I've found a good workshop here that specialise in Jaguars who will look after the car for me, so I'm all set for a long relationship with this car.
UPDATE IN JUNE 2013:
I stand by every word I said about this car three years ago. It is now nearly 16 years old and I have added 22,000 Km in the last three-and-a-half years of (almost) daily use. It has been very reliable. I've had it serviced every 6 months at Roadbend in Perth who are an excellent independent Jaguar workshop. The only failures have been two cooling system hoses (and one of those went on my driveway - convenient!). Apart from that I've replaced the front brake rotors/pads, an engine mount bush and a couple of the coil-in-plug units. I had the headlining replaced, the wing mirrors resprayed where they'd picked up some scuffs, and got the bulb in the climate control display replaced. Last year I bought a new set of Yokohama db tyres, as the old ones were nearly 10 years old and had got hard - what a difference that made! And that's it apart from routine oil/filter changes etc. The XJ is far cheaper to keep on the road than our 2007 Land Rover Discovery 3 (although that too has been reliable).
I recently drove over 600 km in a day averaging just over 100 km/h and got 10.4 l/100km using premium 98 octane fuel. Outstanding.
I'll check back in another three years and give you a further update - I fully expect to be running the car still!