#02#It's been over three years since we last sampled Jaguar's most luxuriant offering, the XJ. Since then the company has been having something of an identity crisis and the business's bottom line has struggled as a result. We drove the new XK a little while ago and came away deeply impressed and imbibed with a fresh optimism for the brand.

Cosmetically the XJ hasn't changed too much over the last few years (as we took delivery of the test car, Jaguar announced a facelift - see here). As you can see in the pictures, the test car came in Sport trim, complete with mesh grilles and wonderfully bling 20-inch alloys. It's hard to assess the XJ's looks compared to the latest competition from Germany. The classical Jaguar lines are the same thing that perhaps dates the car's design, but it remains a clean, distinctive and aspirational design.

It's hard to convey how much of an icon a Jaguar remains. People still stop and nod in appreciation as they drive past and pause to inspect a parked example; it's still a car people promise themselves when they win the lottery or retire. Fortunately the XJ doesn't fail to live up to these hopes and dreams. Once you've finished admiring the external appearance and slide into the interior everything is how you would expect it to be.

Several cows' worth of leather cover virtually every surface of the seats and dash, punctuated with brushed aluminium on the Sport model. The dials and gauges are crystal clear and crisp and all of the switchgear is laid out logically and is lovely to use. The touch screen central control screen remains a strong point, as it is much more user friendly and intuitive than the alternative MMI (Audi) or I-drive (BMW) systems of the competition, on first use at least.

Turning the key in this particular XJ brings to life the 2.7-litre V6 bi-turbodiesel found in the nose of, among others, the S-Type we tested a couple of years ago. We were impressed by its refinement then and left the XJ with these feelings reinforced. It's a marvellous engine that does the badge proud in terms of refinement, effortless performance and, for the first time in an XJ, economy. #p##02# We covered many effortless miles in the XJ and averaged over 31mpg over a mixture of town, country and motorway driving. The way the car gathers speed is incredible. It hardly ever registers more than 2500rpm on the tacho as the gearbox shifts seamlessly through its six ratios, but even at light throttle openings it accelerates with meaningful urge. The engine is happy to rev to its redline smoothly and quietly too and resolutely refuses to sound stressed or harsh.

Most of the time you wouldn't know it was a diesel; there is some combustion noise under hard acceleration, but it never exceeds that you'd find in a petrol derivative, especially the vocal supercharged XJR unit. Indeed, I don't think it would disgrace itself as an interesting XK variant. Where it does mark itself out as a diesel is in the positive senses of relaxed performance, refinement and economy. This is probably the best all-round XJ.

The XJD dispenses of miles in a way that an XJR would struggle to replicate. Utterly unflappable, composed and unfussed a motorway cruise feels almost bizarre, as particularly with active cruise control engaged, it doesn't feel like you have to put any effort into driving. Sure, you are aware of the fact you're moving, thanks to a whisper of wind noise around the A-pillar and door mirror and a hint of tyre noise dependant on the surface, but it isn't draining or tiring in the slightest.

And that's behind the wheel; passengers in the front and rear are truly cosseted in leather arm chaired, air-conditioned comfort. It's a very soothing car to drive, or be driven in. Given that our test car was the Sport model, it's a fair assumption that the normal car would be even more of an effective 'wafter'.

Where that Sport pack pays dividends, as well as in appearance, is away from the motorway. At its best on sweeping A-roads, the Sport flows nicely with plenty of grip, as you'd expect given the footprint of those massive tyres. The CATS (Computer Active Technology Suspension) means excellent body control and a well-judged balance between stiffness for handling pleasure and a supple nature for absorbing undulations and mid-corner bumps. #p##03# It's a decent car to drive quickly with agility and composure that belies its size, but it stops short of scaling the dynamic heights of the equivalent BMW model. Having said that, it enjoys a better ride quality and perhaps more of a limousine experience as compared to Munich's finest.

Whereas we found that the XJR is a fabulous car that finds itself staring uneasily into the eyes of the massively talented BMW M5, the XJD is a car that is much more at ease in the company of the German competition. It is as refined as any of its rivals and has the quality, packaging and kudos to run any of them closer. What it perhaps lacks is that dynamic cutting edge so enjoyed by more modern and contemporary rivals and this is the dilemma Jaguar face. Does the company forego its tradition and brand values and risk alienating loyal buyers in the search of a richer vein of potential sales, or stay true to the brand's more luxuriant and older appeal?

It's a difficult and perilous balance to strike. How do you give the brand a modern, dynamic edge without losing the traditional Jaguar British-ness? One does feel something of a loyalty towards the Big Cat; being one of few remaining British brands, we want the marque to persevere and succeed and with cars as capable as this, the new XK and the forthcoming S-Type replacement, there is every sign that it will prosper. If a luxury saloon with a bias towards comfort rather than dynamic involvement is on your agenda, then the XJD deserves consideration.

---

2007 Jaguar XJ range overview

Model	UK (£ on-the-road)	Ireland: (€ on-the-road)
Jaguar XJ6 3.0 V6 Executive	£43,040	€86,760
Jaguar XJ6 3.0 V6 Sovereign	£49,040	€105,195
Jaguar XJ6 2.7 V6 TDVi Executive	£45,020	€93,085
Jaguar XJ6 2.7 V6 TDVi Sovereign	£51,020	€105,195
Jaguar XJ6 2.7 V6 TDVi Sport Premium	£51,020	€106,735
Jaguar XJ8 4.2 V8 Sovereign	£57,540	€114,110
Jaguar XJR 4.2 V8 Supercharged	£59,540	€143,695