Road Test: Jaguar XK 5.0 Supercharged V8 R 75 2dr Auto

For £4,000, your XKR can now be both faster and more beautiful, thanks to an optional ‘Black Pack' that adds glossy-black 20in alloys, plus more glossy blackness around the windows and grille. Small things, yes, but somehow effective - unlike the optional ‘XKR' decal along the side of the car. It looks nasty, and ruins the XK's lovely lines.

With the Black Pack comes the Speed Pack, which is available on its own for £3,500, but makes more sense when bought with the Black gubbins. It raises the top speed from 155mph to 174, thanks to a re-jigged electronic limiter. It also includes a new front splitter and rear diffuser, a bigger rear wing and more sculpted side skirts - all of which are there to reduce lift and help stability at high speed. The steering system is also recalibrated, to avoid a floaty sensation when ‘making progress'.

So, the Speed Pack's 174mph top speed might give you ultimate top end bragging rights, but you're unlikely to be able to access that kind of pace on a daily basis. Far better to just enjoy the purposeful new image with all the new body bits. The trick, then, is to choose the Black Pack, rather than the Speed Pack alone. It's only 500 quid more and feels more valuable as a combination, especially with that new high-speed stability. A quicker, prettier, more planted XKR? Call that dealer.