A long day behind the wheel of the Bentley Mulsanne Speed called to mind a very grand fountain pen that sat on the desk of a former boss. It was big, almost amusingly so: as thick around the middle as a Cohiba Robusto. It was heavy, too, and obviously expensive, but it wasn’t delicate and ornamental like some plutocratic pens. The materials were fine and the craftsmanship impeccable, but the pen seemed pleasantly usable, as suited to jotting shopping lists as signing peace treaties.

The new Mulsanne Speed is similarly accessible. It is grand, of course, and certainly quicker and faster than an 18ft ultra-luxury sedan needs to be. It is a finely tailored exotic car, size XXL, every bit as pedigreed as a Lamborghini Aventador. Unlike its corporate cousin from Sant’Agata Bolognese, however, the Mulsanne is not a ceremonial car, wheeled out for a few precious miles on sunny weekends. It’s a driver.

The Speed augments the Bentley range in a way that is completely unnecessary but wholly appropriate.

The Speed augments the Bentley range in a way that is completely unnecessary but wholly appropriate. Bentley has a long and storied history of building brutishly fast (and impressively large) cars, and although the flagship Mulsanne, with 505 horsepower and 752 pound-feet of torque, is hardly underendowed, this hotter, pricier version seems just right.

Like the standard Mulsanne (if “standard” can rightly describe a car that requires 500 worker-hours to build), the Speed employs Bentley’s hand-assembled 6.8-litre twin-turbo V8 engine. Output jumps to 530hp and a fairly epic 811lb-ft of torque. Bentley claims this 6,000lb sedan will bolt from zero to 62mph (100km/h) in 4.9 seconds and push on to a top speed of 190mph – believable, perhaps even conservative, figures.

The Speed’s visual cues are subtle; there is no decklid spoiler or Continental T-style flared wheel arches here. Some of the stainless-steel trim bits now feature a darker finish, and the taillamps have lightly tinted lenses. Twenty-one-inch directional wheels are the only obvious visual clue.

And though fuel consumption is doubtless of little concern to Mulsanne buyers, it is perhaps worth noting that Bentley has increased the efficiency of this mighty engine. In both the Mulsanne and Mulsanne Speed, mileage is improved by a respectable 13% – enough to yield an additional 50 miles per tank.

On the road, the Mulsanne Speed is exactly the sort of 800lb gorilla it needs to be. There are big cars that drive small, and we praise them for that. The Audi A8 and Jaguar XJ come to mind. The Mulsanne is not that kind of car. It is a big car that drives bigger. A half-mile away, across a gleaming expanse of hand-buffed hood, a Flying “B” radiator mascot glints in the sunlight. And yet, the squareness of the front end means the corners are always easy to locate, making the car exceptionally simple to position on the road and in the car park. The sedan is nothing close to sports-car nimble, of course, but it is freakishly agile in a sumo wrestler kind of way. The Speed’s considerable athleticism inspires nothing less than awe from its occupants.

The sedan is nothing close to sports-car nimble, of course, but it is freakishly agile in a sumo wrestler kind of way.

Of course, no discussion of a Bentley – particularly a Mulsanne – would be complete without a look at the window sticker. In the US, the Speed starts at $335,600, exclusive of a $2,725 destination charge and a $3,000 gas-guzzler tax. But the Mulsanne is not an off-the-rack automobile. One does not buy such a car; one commissions it. And commissioning is, as a rule, a very spendy process. That radiator mascot? It’s a $3,275 option. Love our test car’s Sequin Blue paint job? Add $5,715. Need a refrigerated bottle cooler between the back seats? Tack on another $10,970. And the Entertainment Specification, which includes a Naim audio system, an onboard wi-fi hotspot and rear-seat entertainment setup with power-deployable iPad tables? That’s $28,760. Our test vehicle carried close to $68,000 in options, for a total price of $408,742.50.

And yet, cars of this ilk float above the indignities of value comparisons. Only those who cannot afford a Mulsanne Speed (this writer, for instance) bother to engage in cross-shopping fantasies or make statements like “For that sum, you could buy a BMW M3 and a Cessna Skyhawk.” Buyers don’t see it that way. To those with the motivation and the means, the Mulsanne Speed is no more interchangeable with lesser cars than my former boss’s pen was interchangeable with a Bic ballpoint.

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