Parkers overall rating: 4.5 out of 5 4.5

If you've concluded that the Jaguar XKR-S Convertible performance was inadequate, you need your head examined. Under the bonnet of this British-built droptop lies a 5-litre 32-valve supercharged V8 that’ll produce 542bhp and 680Nm that’s designed to punch a ruddy great hole in the air. If you plant your boot on the accelerator pedal you’ll get to 60mph from a standstill in 4.2 seconds and if you keep it there you’ll top out at 186mph.

On a dry, smooth road it’s entirely manageable, but on roads where the conditions are changing you can expect a bit of fishtailing from time to time. You have to be kind to the throttle to get the best out of this car, but it’s fair to say that if you aren’t it is a completely awe-inspiring handful.

Jaguar were at pains to tell us that the XKR-S Convertible has as much torsional rigidity as the Coupe, which means that its chassis is just as stiff. Usually, droptop versions of coupes tend to flex more because the roof is missing and, as much as Jaguar would like to tell us that we should get just the same in terms of handling as that of the Coupe, it does feel different.

It feels just a bit more loose than the Coupe, but it’s no deal-breaker. Over bumps and in tight corners it’s not quite as composed as the fixed-roof and if you are driving at speed there is that feeling that you are fighting the car all the time. Still, this is no bad thing and there is a sense of involvement that you get with the Convertible that you just don’t get with the Coupe.

It is marginal and you have to be driving very enthusiastically to notice the difference, but it is there. Like the Coupe, though, you are treated to fantastic handling abilities. The Convertible has well-weighted steering that’s possibly on the light side when compared to say, a Porsche 911 or BMW 6 Series, but it’s got plenty of feel and it tightens up nicely on cornering to give you extra confidence.

The sports suspension does give a firm ride but that means you get vibrant handling. Point the rear-wheel-drive Jag into a sharp corner at speed and it’ll do exactly what it’s told. Of course, if you do push it the tail will step out but not so much that you have to fight it. Overall you get fantastic grip throughout the corner but it’s not boring or so predictable that it ruins the experience.

Make no mistake, this is a proper driver’s car that you need to respect, particularly in changeable conditions. If you charge into a corner on a wet or muddied road at speed, make sure you are fully concentrating and prepare for a bit of correction at the wheel to stop yourself becoming overfamiliar with roadside shrubbery. The XKR-S has plenty of technology that differentiates it from standard models.

As well as a 10mm reduced ride-height there’s the uprated Dynamic Stability Control and Active Differential for extra composure and traction but you can switch that off for a bit of extra involvement. The engine is mated to a sequential six-speed automatic gearbox that you can put in Drive for more sedate cruising, but if you want you can stick it in Sport mode, and change up and down using the steering wheel-mounted paddles.

The Sport setting delays gearchanges and improves increased steering and throttle response for better acceleration. This is where you get to explore the XKR-S’s real handling qualities with slick gearchanges that are also accompanied by pops and bangs from the engine as you change down at speed.