Road Test: Mercedes-Benz SL Class SL 500 2dr Auto

Whatever we might think in the UK, Mercedes-Benz, worldwide, pretty much owns the freehold on luxury sports cars. So it's no real surprise that, within weeks of Jaguar launching a new XK, the mighty paw of Mercedes has reached out to swat it with a power-hiked SL500.

This V8 is the same all-new one that does such a stonking job in the S-Class. It's 5.5-litres and has 388bhp, up from 306bhp, with no harm to the consumption.

It's an absolute lion of an engine that yammers its way to 60mph in the very low fives. But the car costs £75,880, so let's get picky.

First, there's a peculiar kink in the throttle response about a quarter-way through the travel, so it's not easy to pour in the surge as smoothly as you might like. And the seven-speed auto gearbox feels like overkill. There are so many ratios it sometimes can't decide between them.

The better news is that the SL500's active suspension has been further refined: it allows even less roll and body heave when you're pressing on (like this engine encourages you to), but the ride stays comfy on the straights at almost any speed.

The new chassis software is set up to give mild understeer at high speeds, but a tiny bit of oversteer on the way in to low-speed bends.

But it's a subtle enough effect that it's hard to put your finger on what's happening. All you know is that it feels deeply planted on big sweepers but also pretty agile in slower, tighter corners - a place where the new, sharper-ratio steering helps too.

The ESP system is almost magically subtle, but that's not enough to make this a perfect sports car because the steering is too dead.

I wouldn't want to suggest you can't have fun. With all that power and control and such a plush cockpit, you're hardly suffering, are you? Which is why Merc feels justified in charging a price that makes the XK cabrio look like the budget option.

And even if the SL500's new V8 does have all that extra power over the Jag, it is also heavier - so it's swings and roundabouts. In the end, the two have about the same performance per pound sterling.

The SL that matches the XK for price is the V6 SL350 instead. It's good, but compared with the Jag it flounders. This is a car for wafting and posing only. Still, that seems to be enough: by far the majority of SLs sold in the UK are 350s.