THERE are some cars that you struggle find fault with and this high-powered Big Cat is one of them.

OK, there are a couple of things - but we'll get back to that.

The XK is perhaps the car that defines the new breed of Jaguar since it first made an appearance to worldwide acclaim back in 2005.

It has had a few tweaks but pretty much looks that same, which is no bad thing. It is a stunning looking car.

It is also a stunning price especially when it comes to the high performance XKR model.

Not only does it look good it performs brilliantly, particularly the monster five-litre supercharged unit powering this cabriolet.

All curves and power bulges, the 2+2 Grand Tourer sits on huge 20-inch alloys wheels and looks even better as a soft top, its folding fabric roof settling into a compartment that sits just above  the boot in a matter of just 12 seconds, still leaving plenty of space in the boot. That makes for a fantastic open top experience and even allows the tiny seats in the rear to be just about useable for adults - if only for a limited time.

Those seats are really just suitable for children, but that hardly seems to matter.

The interior is a classy place to be and features the signature Jag goodies like the keyless pulsing starter button and the circular gear control knob that rises from the central console when the ignition is switched on and and ambient interior lighting. Soft touch finishes decorate the dash and doors and the plush carpets would not be out of place in a stately home.

If one thing is looking slightly dated these days it is the central seven-inch touch screen controls, but still performs more than adequately controlling major functions such as dual-zone climate control, sound system and communications.

The interior is simply sumptuous with 16-way adjustable soft leather grain seats with memory which are both heated and refrigerated, depending on the weather and heated and electrically adjustable steering wheel.

As for standard equipment, just about everything such as powered door mirrors, auto dimming rear view mirror and cruise control is included, as you would hope for £85,000, but if you want a reversing camera and adaptive front lighting, that will set you back nearly a further grand. But you do get some great kit for the and the Bowers & Wilkins surround sound system temps you to pump up the volume as the risk of bursting your eardrums.

If you like more sedate motoring, then forget the V8 beast powering this convertible. The 510ps rockets the car from a standstill to 60mph in just 4.5 seconds. You are literally thrown back in your seat and the car powers on to a limited top speed of 155mph where permitted.

The power is channelled through a super slick six-speed seqential gearbox which also allows you to you gearchange via paddles behind the steering wheel if you want a little more fun.

The drive is delivered to the rear wheels with active rear differential, traction and stability control stopping the wheels spinning keeps the car on the straight and narrow.

Brutally quick and beautifully refined, the engine note from the twin exhausts sounds like a racing car. It is also well balanced on corners thanks to variable electronic damping of the suspension and when cruising is a comfortably firm ride. Despite lacking a permanent roof, the strong aluminium construction means there is no evidence of body flex.

Those raspy exhausts and the throb of the V8 are about the only sounds you will hear with the roof in place.

The fabric roof has a triple layer laminated construction which keeps the noise - and the weather - at bay.

As you would expect from a supercharged V8, economy is not the most important aspect.

Official figures claim average consumption of around 23mpg. In your dreams if you are too heavy with the right foot. But if you can afford this car, you can afford to fill it up. High CO2 emissions puts it in the highest benefit in kind taxation range as well.

As for the couple irritants? Annoyingly I found the passenger door had to be given a good slam to shut properly and I found the high sill makes it difficult to exit the car, particularly for women wearing skirts as the other half reminded me.