The Golden Benz wasn't worth trading in so I kept it for my girlfriend to smoke about in. A pretty little blonde with a big attitude, she liked blowing the doors off boy racers with it. After she and I split, and after I'd bought my first TVR (in 1996), the Golden Benz became a backup vehicle in my fleet. However, me, Mr D and the Golden Benz were a bit of a love triangle so ultimately, with 215,000 miles on its odometer, I sold it back to Mr D. It's currently (at June 2006) laid up in one of his barns but it will be back some day…

Anyway, back to The Duchess. I guess trying to describe the many features and facets of this car's abilities is as good a place as any to begin auto-journalizing 12 years of owning this wonderful machine.

Short of traction/stability type gadgets (which I hate anyway), sat nav (that I don't need, I am a bloke) and massage seats (WTF?), there is little missing from The Duchess' toy armoury even by today's standards. The Duchess' first owner, a diamond merchant had simply replied "yes" when presented with the options list - presumably to save time, certainly not money. The Duchess cost nearly £70,000 in 1987.

The Duchess has self-leveling, dual-mode hydro-pneumatic suspension that lowers itself at 85mph and automatically switches to Sport mode if it notices the car has been hurled at a corner (smirk). Not only does it have electrically adjustable, heated, orthopaedic sports seats in the front but it also has a pair of electrically adjustable and heated sports seats in the back. And much else besides: split air conditioning, airbag, mighty stereo, electric everything… But the best bit about all these toys is that they are proper electro-mechanical engineering - none of the software nonsense that blights its successors. The Duchess is made with reliable technology. It was created by engineers, not boffins and space cadets. It's the last of the REAL S-Class Mercs, an engineering apogee.

When I bought The Duchess I remarked to friends that I couldn't think what I'd get to replace it. How prophetic those words have proved to be. Truly, my luxo-barge ambitions hit a brick wall in 1993. The Duchess is also the ultimate MPV. Although I prefer "SPV". Captain Scarlet drove an SPV and, as all of us of a certain age know, he is indestructible. Being a couple of metres from the nearest accident, sat behind the world's first production airbag and ensconced in a couple of tons of German armour, that's how I feel.

So what about its multi purpose credentials?

Numero Uno: point to point it is astonishingly fast. Don't believe me? Chase me! The trick hydro-pneumatic suspension, the hefty kerb weight and the sheer brute force of a fuel-injected 5.6 litre iron block V8 casually dismiss the gradients, poor surfaces and camber changes of B roads. At over 85mph, it lowers itself to hug the road - but it doesn't ground out. You'd need a rally clone and big cajones to go faster cross country. For long journeys, it is like a time machine. Aside from the speed, it's the cosseting that means I get out at the other end as fresh as a daisy - The Duchess also dismisses time and distance. How about Spa Francorchamps to Milton Keynes in a cruise-controlled five and a half hours (including two fuel stops and Eurotunnel)? It was a mere four and a half hours after I'd wound the clock back an hour! "Continental GT"? - oh purr-lease. Part of The Duchess' mile-eating capability is its stealth. Midnight Blue doesn't look fast - nor indeed does a 19 year old Mercedes. And that's how she got her name. I once quipped "it might look like a grand old duchess …but the legs of Lynford Christie lurk under the petticoat." [a truly disturbing image- ed] The Duchess bit stuck.

With the coachwork buffed up and a rented geezer in a hat up front, it still cuts a dash at fancy functions for stepping out of the back with a lady in tow. The Duchess has real old-school style that grows with age (corner shop owners have moved on from W126s). It has a huge boot and the big rear doors mean it's possible to carry a washing machine and a tumble dryer. If an object is humanly possible to carry, there will be a way of getting it in The Duchess to bring it home. Apart from the white goods, a 2.4 metre long shelf and a drum kit (in its shipping cartons!) stick in my mind as things nobody watching could believe went inside. I have almost single-handedly helped friends move house with The Duchess.

So that's sports car, limo, business 'tool' and van covered off (and executive jet). How many more diverse purposes do you want? Green? Never mind the gas it gulps, the fact that the energy expended in building The Duchess has not been required again to replace it more than makes up for its thirst for jungle juice. So, yeah, green. Poke yer Prius, beardy.

Then there are the dark purposes that Noddy-like conventional MPVs could never hope to perform. If somebody is daft enough to pick a road rage ruck, the terror of Spielberg's "Duel" is nothing compared with the menacing body language a big dark Merc can muster. It's probably not a facet of my character to be particularly proud of but in this era of sanctimonious finger waggers and 'brake testers' who feel compelled to enforce speed, phone use and various other laws, I find it highly amusing to watch their resolve shrivel when 2 tons of Stuttgart's finest appears to be climbing aboard …however hard they try to make good their escape. Oooh! Speeding now are we Guardian reader? Scurry along! Scurry along! Then there are the odd occasions when disputes have needed settling. Parking The Duchess across miscreants' lawns sets the agenda very eloquently indeed.

I am extremely fortunate to own a number of interesting cars but if I only had one car, The Duchess would be it. It even drifts well. At the risk of "willy waving", I could afford to buy a new S-Class. But why would I? I firmly believe - as do the guys who look after The Duchess - that my 560 will outlive its descendants. I made a pact with The Duchess many years ago that provided its annual running costs stayed below the annual depreciation of a new one, I'd keep on maintaining it. As new ones get more expensive and their depreciation more spiteful, the pact is easier to honour than ever.

In future journals I'll recount the occasions when this pact was sorely, painfully even, tested. You may be able to buy one of these little honeys from eBay for the price of two month's petrol but to run one properly will demand some commitment from time to time. One year, I was in the Milton Keynes main dealer's top ten service customers …amongst the fleets. And that was only my second worst year of expenses. Not for nothing did I earn the nickname "four figure Phil". Conversely, there have been several years in which a service and MOT were the only running costs (last year, with over 200,000 on the odometer, was one of them).

Right now, The Duchess could do with a respray (it's about seven years since I last did it) but mechanically this 223,000 mile 560SEL is spot on. It still pulls nearly 80mph in 2nd gear, about 125mph in 3rd and remains capable of pushing the needle to the very end of the 170mph speedometer. It - she - is one serious motor car.