Overall rating: 4/5

While the headline-grabbing Germans may offer more power and more high-tech options, the big Jaguar XJR super saloon is by far the most satisfying car in the segment to drive.

In the metal 4/5

There's no doubting that the current Jaguar XJ's styling has been at the very least controversial. Many old-school Jag die-hards still refuse to be swayed by it and the rear styling has taken a long time to mellow. But mellow it has and, rather like a laid-down bottle of Burgundy, the XJ's appearance had, to these eyes, done nothing but improve with age. The XJR version's body kit certainly helps, with a deeper front air dam, side sills and a pleasantly subtle boot spoiler. You could argue that some of the add-ons look a little fussy, especially around the front fog lights and air intakes, but it's a handsome beast, especially menacing in a dark colour, and has distinctly get-out-of-my-way looks when it comes up in the rear view mirror.

Inside, the cabin remains as probably the best of any current Jaguar, lifted almost into competition with the likes of Bentley by gloriously thick leather and, instead of wood for the XJR, deep and lustrous carbon fibre trim on the doors and dashboard. Our only complaint is that the touch-screen satnav and infotainment system remains annoyingly fiddly and that Jag has still not caught up with its German rivals in terms of interior and electronic innovation.

Driving it 5/5

If you had to pick one word to sum up the XJR it would be 'smooth'. That may sound rather odd when describing a car that can reach 280km/h, has a whopping 550hp and can sprint to 100km/h faster than most supposed sports cars, but the XJ exudes smoothness from each aluminium pore.

Even on massive 20-inch wheels (anything smaller tends to look a little lost in the XJ's cavernous wheelarches) the XJR rides with a soothing level of comfort and decorum, backed up by seats that feel initially a little narrow and unsupportive, but which improve and feel better with every passing mile. Occasionally, one of those big, wide wheels (shod with bespoke Pirelli tyres) will tramline or skip awkwardly over a particularly nasty bit of road surface but otherwise the XJR retains a level of serene calmness, which its German rivals find hard to match. An Audi S8 doesn't have the ride quality, a BMW 7 Series doesn't have the lovely steering balance and an S-Class Mercedes-Benz is too remote.

What the XJR has is balance, a near perfect balance between an engine that delivers power in deep, long pulls and a chassis that always feels benign, but adjustable. The steering feels remarkably direct for such a big car (and remember, this was the long-wheelbase version we were testing; a model that won't be appearing on this side of the Atlantic) and that bluff nose follows it into apexes like a faithful gundog sticking to its master's heels. Yet it does this without ever feeling nervous. At 50 per cent effort, the XJR feels like a car you could easily drive all day long, or at least until the fuel runs out - which at 25-ish-mpg won't take too long.

Up the effort and the big limo responds. Jaguar was confident enough in the car's ability and agility for us to take it onto the tight and technical sweeps of the Ridge Motorsports Park racetrack near Seattle - the venue for the XJR's launch. Even on the circuit, the big Jag feels at home, sniffing out cornering lines with remarkable precision and settling easily into big, tyre-smoking drifts if you're so inclined. Most impressive of all, despite being pounded around for lap after lap by over-enthusiastic motoring journalists, the cars never needed attention to the tyres or brakes.

In spite of being able to trace its roots back to 1996, the 5.0-litre supercharged V8 engine is still at the top of its game. Emissions of 270g/km might not be too clever in modern terms, but impressively, Jaguar has increased power by 30hp over the existing XJ Supersport model without needing to change the engine's construction or internals. All that has changed are the electronic brain governing the engine, the supercharger settings and the fitment of a more free-flowing exhaust.

That exhaust liberates some truly wonderful sounds too. It's not an American-style bass-rich V8 woofle, but instead a crisper, harder-edged noise, more like a thoroughbred racing engine. It's actually quite quiet, and even with Jag's insistence that it has carefully tuned the engine note for maximum entertainment, you might occasionally crave some more aural fireworks, but refinement is the XJR's primary remit, and keeping the cabin tranquil is something it does very well indeed.

You can quibble all you like with the XJR's lack of the ultra-high-end electronic gadgetry that its German rivals can deploy, but the fact remains that it is without question the best drivers' car in the category.

What you get for your money 4/5

At about €185,000 the XJR seems like quite good value. You get a long list of standard toys including touchscreen satnav, heated and cooled leather seats, adaptive suspension, 20-inch wheels, Alcantara headlining, adaptive cruise control, heated steering wheel, twin sunroofs and more. And it's true that the German opposition will cost more for the same or similar performance and handling. But the Germans can also offer more up-to-date electronics including such items as night vision, on-board internet connectivity and fully active safety systems. Jaguar is still behind the curve in many of these areas.

Worth Noting

The ZF-supplied eight-speed automatic gearbox has a Quick Shift function that makes it feel more like a snappy DSG-style transmission when you're using the steering wheel paddles to shift manually, and it also senses your cornering inputs to help you hold onto lower gears in long, sweeping bends. The suspension is around 30 per cent stiffer than that of an XJ Supersport, and reads the road up to 100 times per second to adjust its damping rates to suit the conditions. Jaguar won't offer a more extreme XJR-S version because it says "more power and more stiff suspension would simply ruin the car." Amen to that.

Summary

Yes, the likes of Mercedes, BMW and Audi can offer you an equivalent car that will be more powerful, more economical and more high-tech, which should leave the big Jag out in the cold. But its combination of gorgeous styling (inside and out), strong performance and a frankly brilliant balance between handling precision and ride comfort mean it's actually the car in the class we'd most like to have on our own driveway.