If you read our report on the facelifted S-Class recently you'll know that Mercedes took the very reasonable approach of not messing about too much with the barge that outsells every other barge. It also out-comforts everything this side of a Rolls-Royce Phantom.

And the AMG pair also outguns everything this side of a Gulfstream G650. None of that has changed, but the facelifted versions of the S 63 and S 65 AMG are now very slightly more efficient and a little safer. You'll be pleased to note that, according to Mercedes, they're still 'effortlessly superior'. And if you want to remember that phrase to tell your friends, think of it as the acronym 'FU'.

There are still two versions then, and you can still have the S 63 as either a standard S-Class or a long wheelbase limousine, whereas the S 65 comes in stretched form only. And again, S 63 denotes a 6.2-litre 518bhp V8 under the bonnet, and S 65 a 6.0-litre bi-turbo V12 with 604bhp and an astronomical 738lb.ft of torque. That one's 0.2 seconds quicker to 62mph than the S 63, taking 4.4 seconds with power sent to the rear wheels through a five-speed auto 'box. The S 63 gets the latest seven-speed 7G-Tronic automatic.

But changes to the transmission (we're not told what, mind), aerodynamics and a set of low-rolling resistance tyres mean there's a three percent fuel consumption improvement across the pair. A figure of 19.5mpg is what you can expect from the S 63 (19.4mpg for the S 65) and a Greenpeace-alienating 344g/km (346).

If you've noticed the exterior changes, well done you. The altered wing mirrors, front LED daytime running lights, chromed grille and new front apron are all hard to spot, but they tidy up the aesthetics subtly. More significant is that the new bits of useful safety kit are now standard too, comprising Attention Assist, Night View Assist and Distronic Plus. Respectively, they warn you if you're about to nod off, help you spot moving objects on dark roads via an infra red camera and warn you about obscured objects close by using radar sensors.

All that stuff is standard, but it's not free because Mercedes has put the prices up slightly, with a 'bog standard' S 63 a smidge over £96k and a stretched S 65 just under £150,000.