Let's face it, the drive from Dublin to Galway has to be one of the worst in the country in main road terms. Even with the various bypasses of some of the main towns, including Athlone, it's a slowcoach drive most of the way, made worse by the paranoia which many of us are suffering because of penalty points.

Don't get me wrong, I'm not advocating a speeding carte blanche, but it is noticeable that there's significantly more traffic 'clumping' now, at in or around the national speed limit, and it makes it a lot more difficult to overtake because there's what was many years ago described to me as a 'string of sausages' of vehicles all together with no real gaps between them to allow a safe overtake.

And even if a piece of road long enough and clear of oncoming traffic comes up, many of us are still scared to put the boot down and get beyond the problem string, on the basis that this will pump up our speed to maybe 75mph and that will be just the moment that one of our good men in blue will pop out with the hairdryer and do us.

So, even though I had the power, and the glory of a Jaguar XJ under me, this particular recent journey across the country was pain. Dulled somewhat by the comfort of leather and wood and a smooth autobox, true, but painful nevertheless.

But there y'go ... into each life, some rain must fall. Or a traffic queue must occur.

The car in question was the XJ6, the 'entry-level' version of the flagship of the Jaguar range. And a very innovative model, too, being the first Jaguar ever to be constructed almost entirely from aluminium.

Not that you'd know, of course. While the one they revealed at the Paris Show last year was all polished and shiny aluminium finish, the production versions come painted as usual, this one in a very fetching burgundy metallic which gave the car the rich appearance it deserved.

The essential shape of the XJ hasn't changed in principle since the car was first launched, but as it happened I drove behind a decade-old one on that Galway trip, and the differences were very obvious. If no other than size, but also in what I might call svelteness. The XJ has ... grace? Yes, grace. And the allied epitaph of elegance. It doesn't try to be a hotshot highpowered sports car, despite the heritage, but is a true luxury saloon with a sporting pedigree.

The length of the current car really emphasises this. Long body and a not very high roof makes for a very sleek silhouette. The wheels on the review car were also rightly styled for the proportions and the side view of the latest XJ is taut and compellingly beautiful in a timeless way.

Inside is traditional Jaguar plush, all light cream leather and lots of dark wood veneer, richly varnished. And all electrics in this car's case, too, with both front seats and even the steering adjustments all electronically effortless. As is a pedals adjustment. There are three memory buttons for the driving position, each of which can be set to all adjustable bits to the taste of multiple drivers.

And when you switch off the engine and take out the key, the steering wheel moves up and out of the way. Good this, because I liked the steering wheel best down fairly close to my legs in this car and getting in and out would have been a bit awkward.

Despite the low roofline, there's more than ample headroom, and that's both front and rear. Important, because this one is as likely to be chauffeur-driven as it will be by the owner. For all occupants, comfort is absolute, though perhaps there isn't as much rear kneeroom as in more plebeian offerings such as Opel's Signum.

Still, there's the swish factor, isn't there? And the inevitable attention that will be given, whether in envy or in admiration, as one does that swishing by.

Back to accommodation, and the boot is long but not high, able for the golf clubs but not cases on their ends. But there's enough space so that sir and madam do not have to rely on the overnight bags.

Under the hood, we're familiar with the V6 AJ engine already used in both the S and X series cars, as their middle and upper power ranges respectively. In the XJ it pumps out a smooth 240hp and propels the machine to 100 km/h in a tad under 9 seconds. It does the critical 50-100 km/h very comfortingly in less, at 8.4 seconds.

Given the circumstances in which I had to cross the country, I didn't have much chance to punch the go-pedal, but when I did there was a reasonably swift response when I was mildly enthusiastic. But it became a little more fun with a solid flooring and a twitch from auto to manual on the J-gate to hold it in gear, and as the revs rose there followed an exceptionally pleasant and increasingly insistent growwll. Very serious cat sound. With appropriate lithe leap forward.

OK, not at all the real jump that the supercharged 4.2-litre can do, but quite adequate for most of us, and better than in many other cars.

Of course, only a very small proportion of the 145,000 buyers of cars this year will be able to buy one of these anyway, so the comment is rarified.

But we can all aspire ...

Anyway, there's the matter of whole costs in running a car, and it is a truism that the larger your Jaguar (or any big car) the quicker it loses its purchased value. And looking at the projections for the latest XJ, buying the 3-litre can mean that it holds its value by 10 percentage points more than the more powerful and more expensive V8 versions over a three-year period.

Over a week with the XJ I have to say I was impressed with the fuel economy, which on the cross-country run was easily in the high 30s and generally, including a fair bit of city driving at 9-14mpg, worked out at around 29mpg overall. For this kind of car, not bad at all. There's no diesel yet, but once the new large Peugeot/Ford diesel comes available next spring in the S-Type, I think we'll soon after have it an option here.

The other mechanical aspects of the review car also came out positive. The 6-speed autobox is as smooth as they come, and when used in the 'manual' way changed quickly and fusslessly.

I came back from Galway by a different, more challenging and more satisfying route, which didn't make me up any time but did reduce the danger of falling asleep from boredom.

And, on twisty ways with clear roads and good visibility it was possible to see if this sporting limousine had what it takes to handle well off the straight and narrow.

And, you know, it did. Not with the preciseness of an MR2 or an MGTF, but that's not the point and wasn't the trial.

The brakes were really good, too, after I got used to the fact that very little extra pressure brought in some kind of assistance, which made my slowing a little choppy at the beginning.

Bottom line, would I buy this car?

Mmmm ... no. But that's not because, if I could afford it, there's anything wrong with it. I'd be spending a little less, and buying the X-Type diesel.

But that's a whole other story.