Like the Fiat Panda at the opposite end of the Pcoty scale, this big limo could seem a bit out of place in this contest, to the untrained eye. It weighs two-and-a-half tons, has just about every pampering gadget you could possibly fathom, including reclining rear seats perched behind acres of legroom and built-in TV screens.

But if you have an inkling of enthusiasm for fast driving, you?re not going to give Jeeves much time behind the wheel. Under this bonnet, there could just as well be nuclear power. Merc?s 6.0-litre bi-turbo V12 pelts out an incredible 450kW and sends an almost unbelievable (yet still electronically limited) 1000 newton metres of twisting power through the drivetrain. It?s little surprise that under hard acceleration, this Merc feels like it?s going to take off like a Boeing.

It does feel somewhat like a 747 in the way it goes about its business. It?s just so silky smooth in the way it delivers its power and pulls the car along, occupants could be forgiven for not noticing that their internal organs are fighting for their rightful position. And against the clock, S65 is the second fastest car here. It ran from 0-100km/h in just under five seconds and once on the boil, overtaking acceleration is just phenomenal.

Performance might be from the top league, but you would never expect much agility from a car of this size and bulk. It?s pretty obvious that this is where this car would fail as a driver?s machine, but in truth, S65 is not bad for what it is. With a state-of-the-art chassis, also featuring Merc?s Active Body Control system, which aims to minimise roll and provide a sportier feel, it delivered a surprising lap time around Kyalami. Not quite in the top league, but close enough and more than we?d expect from such a heavy limo.

Bear in mind, though, that with this monstrous power, bulk and rear-wheel propulsion, this car will be downright dangerous in the wrong hands, especially if the ESP traction control is switched off.

For a price that?s well short of two-bar, the S65 is a spellbinding package. If you?re prepared to live without the snobbery rights that a Rolls Royce or Maybach would bring, and instead seek a sporty limo that you?ll actually want to drive every day, there?s nothing to touch this grand flagship of the three-pointed-star range. Sorry Jeeves.