Bentley's GTC Speed has got your number

On the prowl: the Bentley GTC Speed may be a 200mph soft-top, but it'll be driven slowly in cities by narcissists. Photograph: James Royall

BENTLEY GTC SPEED
£153,400
MILES PER GALLON: 17
CO₂ PER KM: 396 GRAMS
GOOD FOR: SHOW PONIES
BAD FOR: PIT PONIES

If you've ever arrived in London from the west via the great maw of the M4, colliding with the congested capital like a piece of arterial plaque swirling into a diseased heart, you may have found yourself edging down towards Chelsea. You'd have hit the river – and standstill traffic – at Cheyne Walk and, if you were still in touch with your senses, you might have noticed on your left two Bentleys which are usually parked in an open-fronted private garage. Their number plates read 2B and NOT 2B. Plates such as these sell for huge sums. A few months ago 1O went for £210,242. A personalised plate is the ultimate accessory for the super-rich car owner. I knew I had to start looking for a new dentist when the one I'd been seeing for years bought GOB 1 for his Porsche – a shade of dark grey that reminded me of my fillings. And, true or not, Peter Andre's gift of BO55Y KT for Jordan's Range Rover must have been worth every penny.

Research carried out by the insurance company elephant.co.uk shows that if you are the owner of a nursing home, live in western Stirlingshire and own a Ferrari 360, you will almost certainly have a personalised number plate, because that's the occupation, location and vehicle which have the highest percentage of personalised plates in Britain. Incidentally, if you are a janitor, live on Merseyside and drive a Ford Orion you will almost certainly not own a personalised plate.

This week, I've been driving a Bentley with the number 2000TU. TU was a local registration plate for the Chester area and Bentley own a dozen or so "cherish plates" with this suffix. They also own 1 WO and 21 WO – the WO standing for Wilfred Owen (Bentley), the founder of the historic marque. During a long sunny weekend in the Bentley, plenty of people stopped and stared, but I don't think it had much to do with the cherish plate and everything to do with the fact that the Bentley in question was a pearlescent white convertible with "smoked" low-pro 20in alloys and a Glastonbury-sized stereo.

It's impossible to sit in the 200mph, 6-litre, twin-turbo, 600bhp, two-and-a-half tonne tourer without being in two minds. On the one hand, it's the epitome of limitless power and budgetless motoring. On the other it is an expression of unmatched vulgarity and over-the-top excess. There is no justification for its dreadful fuel consumption or poor emissions record. The Speed variant costs 20 grand more than its standard GTC cousin, and for that you get 15% more power, nicer seats, bigger wheels and wider exhaust pipes. Given that it stood out on my suburban street like Lady Gaga at a Women's Institute cake sale, I was braced for abuse. But all I got was a steady stream of "Nice car, mister!", "Good choice" and "That's the car, man!" My wife had two women come up to her and cheer, "You go girl!"