For centuries wealthy men have worn tailor-made bespoke suits. But now some of the greatest fashion houses offer top-quality menswear as well. Our Hedonist sees how they measure up

Is bespoke best when it comes to suits? The answer would seem to be self-evident: a bespoke suit is fitted to every curve and eccentricity of your body. How could anything come close? Yet some of my favourite suits are off-the-peg. Tailoring is shrouded in myth, and for me it was only recently - when talking to some insiders at a menswear show - that the penny dropped.

"If you buy off-the-peg from a top fashion house, you are getting something designed by the world's best menswear designers, even if it's not made for you," one of the insiders pointed out. "If you buy bespoke you are completely at the mercy of your tailor."

So in an attempt to find out the definitive answer for you, I went back home and ordered two suits. The first was a Su Misura from Ermenegildo Zegna. The second was a bespoke number from Rubinacci on London's newly most fashionable street, Mount Street in Mayfair.

Zegna has the best pedigree of any men's fashion house. This giant family-owned company leads the way in wool microtechnology and produces cloth that is sold to other fashion houses. Su Misura is their made-to-measure range. It involves changing a standard off-the-peg item to your measurements. The style and cut are Zegna; the detail of the fit is yours.

I chose Trofeo, their most famous cloth, which is a worsted fabric made from Zegna's trademark superfine Australian merino wool, each fibre less than 17 microns thick for an utterly luxurious feel.

Classical and unshowy, in a mid-blue, the abiding characteristic of this three-button suit is the wondrousness of the cloth. It's a beautiful, formal, structured business suit, and yet it's so comfortable, so gentle and so right I could sleep in it. You forget you're wearing it, which is the biggest compliment a man can give his suit.

In contrast Rubinacci is a small Naples-based tailor, run by Mariano Rubinacci, which pioneered the internationalisation of the unstructured, lighter Neapolitan style - a style that inspired Giorgio Armani's signature unstructured suit coats decades ago.

It took five fittings and measurements of parts of my body I didn't know I had before my Rubinacci suit was painstakingly put together. Rubinacci's style is a contrast to the classical Zegna suit. The suit coat is unlined, for summer wear and for comfort. The fabric of the sleeve is gathered against the shoulder, giving a distinctive look; there is little padding so you feel curiously free. "It's like wearing a cardigan, not a jacket," says Mr Rubinacci. The feeling is lovely.

Stylistic touches include a curved out-breast pocket and cuff buttons that jostle with each other informally. Once it was on, I didn't want to take it off, and Rubinacci's presence in Mount Street, a few hundred metres from the formal fiefdoms of Savile Row, is a reminder that a fine suit need not be a burden that the wearer must endure.

So which is better? Both are perfectly attuned to my body shape. But in a slight reversal of expectations, I'd wear the Zegna to a formal business meeting and swap into the bespoke Rubinacci, with a knotted silk tie, for a hedonistic evening party.

DARIUS SANAI is the Editor-in-Chief of Condé Nast Contract Publishing in the UK and runs his own businesses