The bad news is that I fear my tailor may never speak to me again. The good news is that I may, at last, have earned my bank manager’s undying admiration.

The cause of my sartorial downfall and financial triumph? A £25 suit from Aldi, the German-owned discount supermarket.

It is not just any £25 suit, mind. It is a two-piece pinstripe which, Aldi claims, will banish for ever the stigma of wearing a cheap suit - and help cash-strapped office workers to beat the credit crunch. The fact that it is being launched shortly after Aldi signalled that it was beginning an assault on Middle England is no coincidence either.

Aldi, which insists that its “Business Suit” is classier than its other cheap rivals because it is made of a mixture of viscose and polyester rather than 100 per cent polyester, may be feeling confident. I, however, am feeling a little nervous, not to mention itchy.

My nervousness derives from the fact that I am test-driving the suit at the Connaught Hotel in Mayfair, London - a bastion of wealth and privilege, where customers are not expected to wear suits that cost less than the afternoon tea (£28, plus service).

When I arrived, even the hotel’s longest-serving staff could not remember when they last let quite so much man-made fibre through their doors.

“Am I smart enough for the Connaught?” I asked my waitress, still bristling at the memory of the time I turned up there without a tie and had to be kitted out with some egg-stained monstrosity that the concierge kept for such emergencies. “Oh yes,” she said, without the slightest hesitation. It takes years of training to hide your withering contempt as well as that.

And did I say itchy? Well, the suit may not have the giveaway sheen of most polyester clothing, and it may even be machine-washable, but there is no escaping the fact that polyester and viscose do not have the same feel next to the skin as the finest worsted.

It is, however, remarkably popular. My first attempt to find one took me to the Aldi on the Old Kent Road, where I found the suit between the instant mashed potato (49p) and the Premium Functional Dog Biscuits (£1.49). Plenty of suits, but they didn’t seem to have any in my size. “Sorry,” said Kay, the deputy manager. “They are selling out really fast.”

“Could I try one on?” I asked her. She gave me a look of mild concern, then said patiently: “No, but you can bring it back in up to 30 days.”

On to Catford, where the suits - sold separately, with the jackets £16.99 and the trousers £7.99 - were attracting admiring looks.

A middle-aged man in a tracksuit said to his friend: “Look, 17 quid for a jacket, then you’ve got the strides for another 8 - well, you’ve got a suit for a pony. That’s not bad.”

Back at the Connaught, I managed to reach the end of afternoon tea without being rumbled as a polyester-clad fraud. I asked the Times photographer how it looked.

“Not too bad,” he said. “In a darkened room, you wouldn’t even know.”

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