MENTION cool-looking, super-fast Jaguars and names like the E-Type, new F-Type and mean machine XKR spring to mind.

But there's a Big Cat lurking in the line-up with the razor-sharp claws to scratch the lights out of its rivals' sockets.

The 5.0-litre V8 Supercharged XJR doesn't merely sit at the top of the XJ luxury saloon range, it's the most powerful ever.

This is a car that really turns heads. Wherever you drive or park, people want to stop and ogle at the low-slung, lean lines of the Jaguar, with its red brake callipers, 20-inch wheels and black honeycomb radiator grille.

Of course the vast majority of XJ owners are going to be driving the 3.0-litre petrol or V6 diesel models - outstanding performers in their own right.

It's some feeling though to know you're behind the wheel of a big cat with a bite like no other. Take the XJR to a track day and you can appreciate the rush of hitting 62mph from zero in 4.4 seconds.

For a big saloon that's sensational, as is the knowledge that the 550bhp Jaguar can blast on to 174mph - higher still if the top speed wasn't restricted.

And while that sporting intent is certainly not understated, it is nonetheless delivered with time-honoured British panache.

Leather-clad and luxurious, there are R logos embossed in the seat-backs, piano black and chrome inserts around the dash and a TFT instrument panel that lights up with the leaping Jaguar emblem.

Depress the throttle and there's a perfectly measured snarl from the engine and quad tailpipes. In fact it is testament to just how accomplished the XJR actually is, that at no point did it feel anything other than beautifully poised, smooth and planted on the road. Nor was there the slightest hint of wind noise.

You can travel at half the speed in some vehicles and feel like you are about to take-off; that was never an issue here.

Multi-adjustable seats in stitched softgrain leather, concert hall quality sound, loads of interior space and all the electronic wizardry you could imagine are there in a car that puts Jaguar top of the pile.