I have discovered a downside to personal tailoring. Only the one, mind. Once you've experienced the delight and pleasure of having a suit made exactly to your measurements, one that fits you where it should and leaves room where it needs to, with your own customised touches, you'll never look back.

That moment you slip on the jacket, and the sleeves are perfect, the body is subtly brought in at the bottom of your ribcage, is on a par with the first time you drive a luxury car.

If Armani is the Ferrari of tailoring, then Gieves & Hawkes is the Bentley of bespoke. Or should that be Mini?

"One of the reasons for the success of the Mini is that you can customise it, have a checked roof and the like," says Richard Baker, store manager at Gieves & Hawkes in The Mailbox.

"It's the same with personal tailoring; a lot of people can afford a £600 suit - especially if it's on credit - and it's not so much the fit - we can get an off the peg suit to fit you really well; it's the individuality of personal tailoring; having it made to your requirements, it's something that says something about you."

Of course you may never have had the thrill of driving an Aston Martin DB9, Bentley Continental GT - even a Mini Cooper S for that matter, but chances are you've thought about it, fantasised even.

Flicking through the dozens of bunch books at Gieves & Hawkes is like leafing through the contact sheets from Cameron Diaz's latest swimsuit shoot.

There are over 4,000 different cloths to choose from; pinstripe, birdseye, hopsack, Prince of Wales check to name but a few variations. Then there's the matter of choosing the weight of cloth - generally either 9oz, 11oz or 13oz.

And what about the yarn count? Each cloth is classified according to strands per inch, so it's a choice between the 80s, super 100s, super 120s, or even super 130s. They only get called 'super' when it's over 100.

If your head is already swimming, don't despair. Happily help is at hand in the shape of your very own personal tailor, in my case Richard, manager of the Gieves & Hawkes store at The Mailbox, one of 23 outlets the company has nationwide.

Brummies lead the way in personal tailoring; where other stores might sell one personally tailored suit each week, Richard and his team take orders for around four or five every seven days.

So what is personal tailoring?

Simply put, it's having a suit made to your exact requirements and measurements, with the measuring process based on an off the peg 'blank' which roughly conforms to your size. The basic pattern is then altered and tweaked, as well as the options to customise the suit in terms of how many buttons, pockets, lining etc.

While not as detailed and expensive as a bespoke suit (where a personal pattern is hand-drafted and hand-cut), personal tailoring will cost a third of the price and not much more than a very good ready-made article.

At Gieves & Hawkes the personally tailored suits are priced from £695 to £1095, (the price based on the cloth used), but everything else is included in the price, including the one to one service, attention to detail - and a fine cup of tea to boot.

The Birmingham store has a dedicated personal tailoring area, complete with leather armchairs and flat screen TV showing films featuring such style icons as Steve McQueen and Sean Connery.

Here Richard or colleague Tim Abela will take you through the whole process, which takes around half an hour.

"The first thing we tend to ask is what the customer wants the suit for," says Richard. "Is it for a wedding or do you intend to wear it to work and sit on a train for three hours a day."

I opt for something to wear occasionally, a maximum of once a week, but before I flick through the bunch books, it's time for the tape measure to come out.

This is the downside I mentioned earlier.

Back in September 2002, you see, I had been measured for a Gieves & Hawkes suit, a very nice single breasted, two-button dark blue pinstripe. I still wear it, and it still draws plenty of favourable comments.

No, the downside is that Richard still has my records from five years ago - as he does for every customer who's ordered a personally tailored suit. As he takes the string of measurements - chest, waist, jacket waist (a good inch and a half less than the trouser measure), hips, seat, inside leg, half back - I feel like I'm back at school waiting for my A-Level results to be posted up on the board.

The good news is I have only put on half an inch on my waist and an inch or so on the seat (extra muscle, obviously).

It's a delight to watch him in action and explain the different nuances and idiosyncracies.

My shoulders and back are quite square, for instance, so he makes a note to 'spin' the shoulder head forward and rotate the top of the sleeve. For the half back measurement (8 ½ inches), Richard says he'll take off 1/8 inch to remove the small dip in the cloth between my shoulder blades. These are subtle tweaks that you might not notice on an off the peg, ready to wear suit, but when it’s pointed out you then appreciate just what they’re doing.

Once the measurement sheet is complete, we sit down to settle on the configurations.

Two or three button jacket? (95% of suits sold are two-button). Single or double-breasted? Flat or pleated front trousers? Back pocket on the trousers – if so which side?

“You should never keep your wallet in the backpocket,” Richard advises. “It will just wear it out.”

Zip or button fly? Straight or slanted pockets? One or two back vents on the jacket?

At each stage, Richard happily tells me the reasoning, pros and cons behind each variation; straight seam pockets, for instance, tend to open a little when you walk; pleated fronts tend to be more popular for comfort at work.

It’s all subtle nuances that you and I might not think of or realise – these guys have been doing it for hundreds of years. Gieves & Hawkes, that is, not Richard, though he and his team have a good few years’ experience between them.

We’ve decided on a dark navy super 120s hopsack cloth, a two-button single breasted three-piece suit (four months into 2008 and G&H have sold more suits with waistcoats than they have in the last five years).

Fast forward six weeks after my first visit and the suit is back. It is fantastic. The gold/blue paisley lining (which is also the same cloth for the waistcoat back) is distinctive but not ostentatious. The jacket slides on, the sides sculpted and curved, the cuff buttons that actually work – all trademarks that this is no off the peg number. Every customer will have this second fitting just to make sure the suit sits as it should. Richard instantly comments that the trousers – with their cavalry slope front (ie they come out a little at the bottom) – could do with an extra 1/8 inch on the length, while the sleeves show a little too much shirt cuff. Both will be tweaked by one of their approved tailors in Birmingham, the suit back in a matter of days.

No wonder then, that after working for Gieves & Hawkes for five years, Richard admits he can’t shop anywhere else – no other tailor’s suits match up to one of their own. He has a rack of G&H suits for work at the back of the store, as commuting in them is one of the big no-nos (see his top tips above). I have two now. And counting...

* Gieves & Hawkes, 44-46 Wharfside Street, Birmingham. Tel: 0121 632 5295