Kevan Richardson, programme manager at Jaguar Cars, says the new XKR-S is a duality, it has dual identity disorder. Might I suggest multiple identity disorder? Let\'s begin to divulge why. Jaguar is boasting about this car being the most powerful model it\'s ever made. Isn\'t that a bit like Range Rover saying it\'s finally succeeded in making the most off-road-incapable SUV ever? I know, crazy, right? Power doesn\'t a Jag make. How about price? The XKR-S will cost, when it arrives here in November, as much as a nice Aston, Porsche Turbo S, a wild Maserati or even a full-blown supercar. But of course the XKR-S isn\'t as good as a Ferrari, Lamborghini or an SLS AMG. Now that we\'ve sifted away that lot, please join me in the pits of Portugal\'s Algarve race circuit so we can enjoy the best Jag ever. Not since the XJ220 has a Jag cost so much (although the XKR-S still isn\'t nearly as costly as the $500,000 (Dh1.83 million) Nineties sensation), and not since ever has a Jag made 542bhp, and not since Le Mans 1990 has a Jag been so fast. Yet at the same time, the XKR-S is so… Jagly. Jagish… No? Jaguatarian. It achieves a lot of great things, this one. The engine isn\'t half special either. I\'ve never understood how the Yanks acquired the whole, \"We are the masters of the supercharged V8\" thing. The Brits have been doing engines with capacities rivalling cargo ship containers since the Twenties, and sticking supercharges on them too. Remember the Blower Bentleys? Of course you don\'t, your grandpa was only a kid back then. How about \"there\'s no replacement for displacement\"? Carroll Shelby? Mickey Thompson? Or perhaps Fred Duesenberg? Wrong: that quote was famously uttered by one Walter Owen Bentley. It seems the Brits are the first Yanks in more ways than one. Which makes this XKR-S the true modern muscle car. How many personalities is that so far? Why it is what it is Jaguar is a vibrant company these days. And remember, this is a carmaker whose last XJ looked like a Fifties model with big wheels. Jag\'s clientele smokes pipes and owns slippers for the occasion. They think a laptop is a knitted legwarmer. The new 542bhp XKR-S scares this traditional old clientele witless. This is not the same antique Jaguar. For years, while the buyers grew older, Jaguar went the other way, reinvigorating its youth. Think of early Jags and what pattern do you get? Speed. SS100, XK120, XK150, E-Type... And then, nothing. Jaguar slumped into its rocking chair, and waited for the medicine to run out. Even the XJ220 happened generations and generations ago. But you look at the line-up today and you wonder how Jaguar discovered the fabled fountain of youth before anyone else. Every model is still unmistakeably Jag. Jags don\'t need to look old to be true to the brand image: in the Sixties the E-Type didn\'t look like it belonged in the Fifties. It was ahead of its time, in styling and performance; it had disc brakes and things. So there\'s no reason why this, kind of found-again, Jaguar, shouldn\'t go a little crazy once in a while. And multiple personality disorder is, you know, pretty darn crazy. If not exactly right off the bat, finally I can tell you why the XKR-S is so good. It does road, track, and that thing old Jag devotees like so much, which can be best summarised in one word: boring. Of course you must realise that you have a choice with the XKR-S, unlike, unfortunately, most other crazies. Jaguar has accomplished this blend, or rather this wide polarity, starting right at the beginning. The XKR-S wears a British bulldog\'s mug. See? With the drooping cheeks you get the whole typical Brit iconic thing going, but sadly it ends up reflecting the ugliest snout in the canine kingdom. It sure looks mean though, with all those vents, flics and intakes disturbing the classical flow of the XK\'s svelte panels. You also can\'t have this Jag in British Racing Green, but you can have it in French Racing Blue and Italian Red (Whaaaaaaa?!?). And not even a termite colony would sniff out any wood inside; it\'s all dark leather with clashing stitching and lots of sporty things like aluminium and carbon-fibre look knitting. And then, the most un-Jag thing you can imagine, a wing, not even in body colour, and with slats in it. Yes, that\'s how adventurous Jaguar\'s been here. You can also have the wheels painted black, which in the modern automotive culture denotes absolute sportiness somehow... Track tested The past few paragraphs sound like an RS model of Porsche\'s. But then comes the biggest piece of Jaguar DNA yet — the power. Like the car itself, the XKR-S\' 5.0-litre V8 engine is aluminium, nestling a twin vortex supercharger within the banks of its cylinders. With a remap and increasing the exhaust gas flow the motor easily hit its power figure and 680Nm of torque. The impressive bit, though, is the linearity of the power and its response on your right foot\'s demands. With its variable timing system (all four cams) the engine spikes up the rev range from any rpm, immediately waking up to the merest tickle of the throttle. Jaguar says this is its most responsive engine ever, and I believe every word. Through the six-speed gearbox running the ponies to the rear wheels, the power twists and claws its way down the strip for a 0-100kph run of 4.2 seconds and a top speed of 300kph. The transmission is, of course, automatic; another aspect keeping with the nature of Jaguars. If I could take one thing away from lapping the Algarve circuit, it would be how scary the circuit is, while the car itself never made me sweat once. The track winds its way up and down blindly, hiding all its apexes, or at least leaving them ludicrously late. It can all go very wrong here, but at the wheel of the XKR-S it never even came close. The engine\'s flexibility is such that I didn\'t even need to bother what gear I was in and just drove it out of slow corners and up the steep slopes like a diesel — torque baby! And in the tight sections the instant response of the V8 lets you pivot the car around its axis by manipulating its weight balance precisely. It\'s very easy to drive despite the roar of the exhausts and the screech of the supercharger. That\'s not to say it\'s not exciting... Jaguar\'s teamed the limited slip differential with the car\'s electronics and stability systems, so that the diff reacts electronically rather than clunking you into line mechanically. Coming out of a bend too hot, the LSD does the first reaction while you go, \"Hm, must turn the opposite way now for a bit,\" and then you compute and finish it off. Think of it as an alley hoop slam dunk — the diff creates the play and passes the ball, you smash it home and get the glory. And most wonderfully, there\'s no slow corner understeer that\'s so common with aggressive LSDs. The XKR-S drivetrain is incredibly well balanced and sorted for beginner and novice drivers to enjoy and have fun manipulating. Despite the electronics, this is still very much a car that needs its drivers\' precise inputs to thrive, and that\'s why the XKR-S manages to feel so mechanical in a digital age. And then you take it on the bumpy, badly cambered and unmarked roads around the Algarve and the British bulldog suddenly turns into an obedient Border collie.The suspension — you have levels of traction, damping and response control — swallows bumps like a black hole, acknowledging them, but simply eradicating them. The car is stiff and rigid, yes, but there\'s no juddering or any unwanted play in the steering wheel. Really, it\'s no different from a normal XK. It just produces much nicer noises every time you overtake a tractor. But then the Jag\'s third, boring persona comes out a wee bit too. As composed and liveable as it is on the road, the engineers couldn\'t help themselves from dialling ina little of that old-world Jag charm. The softness of the assisted steering is almost detaching from the experience, and the unsprung feel of the pedals — which all just fall flat to the floor if you so much as think of pushing them — point at a car that\'s not meant to go fast. But this goes very, very fast, and corners so evenly you\'d swear it had all-wheel drive (no, it\'s just that clever diff). So some more feedback could be quite helpful in keeping you out of the Mediterranean Sea just to the right down there.