A business class-only service between London and New York hopes to fill the gap left by Concorde. But can it make up in luxury what it lacks in speed? Andrew Buncombe climbs on board to find out

Stepping aboard Eos Airlines, the first business-class only scheduled carrier between the UK and the US, is like entering a somewhat austere but fashionable New York restaurant. The colours are muted greys and black, there are red roses, and the staff are dressed in navy and black suits and - unlike in many New York restaurants - they are terribly friendly. It feels exclusive.

And that is the point of Eos. David Spurlock, a former British Airways senior executive and the company's founder and CEO, says he is aiming to provide unparalleled comfort and professionalism. When he enthusiastically launches into his marketing spiel he claims that his customers tell him his new venture surpasses private jets for its level of comfort. The three Boeing 757s Eos operates have been stripped of their 200-plus seats and instead fitted with just 48 beds that fully recline into a 71-inch flat bed. There are cashmere blankets and real pillows and head-rests covered in faux suede. There's a personal DVD player programmed with about 15 movies and other stuff. In terms of comfort it's similar to BA's industry-leading business class, Club World.

But with the inflight service, Eos probably has the edge. The meals are served on real china with real cutlery with nice linen and real glass. On the day I flew there was a choice of two starters and three main courses for the main meal with a service of sandwiches and cakes an hour before touching down in New York. Both the grilled goat's cheese and asparagus salad and the fillet of beef in a peppercorn sauce were really splendid.

Spurlock says his new airline has been getting rave reviews, but if you're going to organise swanky trips to New York for the media what do you expect? What really matters is what the paying customers think, and on this flight there were just a handful.

Half way over the Atlantic, I ambled down the aisle and spoke with Mary Ann Wheaton, a CEO of a fashion house. She was returning to New York after a meeting in London and had lots of praise for Eos. "It's really very comfortable," she said. "And they really looked after me. It's like having your own private restaurant." Ms Wheaton is no stranger to transatlantic travel. She used to commute between New York and Paris by Concorde, she said glamorously, but she claimed Eos was more comfortable than traditional multi-class operators because passengers were not "inundated with screaming kids". If she had one criticism it was that the plane services Stansted rather than Heathrow. "The other morning it took two hours to get into London."

Amid this easy travel on an airline named after a Greek goddess, and the buzz of the champagne cocktails, it's easy to forget there is another side to these flights. Given that each Eos flight is only equipped to transport 48 passengers in a plane designed for more than 200 there is a big question about the environmental impact. Richard Dyer, a campaigner with Friends of the Earth, says: "Each return passenger on this new Eos service will produce four tonnes of CO2 while enjoying a tax exemption of £1,000 because aviation fuel is tax-free. This is economic and environmental madness." When I asked Spurlock about this he suggested that his airlines were, per passenger, actually more efficient than the bigger planes that offered a variety of classes. It made no sense to me and when I asked him again his explanation appeared no more convincing.

Once the opening discount of £1,000 expires, a return flight on Eos will cost £3,555, about £700 less than the full business-class fare on BA or Virgin Atlantic. MAXjet, another business-class-only airline that starts on the same route next week, has an initial return fare of just £854 - though without the flat-beds. Is it all worth it? Of course, if someone else is paying it's an utter delight, but while Eos and BA's business class are terribly comfortable you don't actually arrive at your destination any quicker than the people in economy. And on a day flight to the US you'll still find yourself flagging by early evening as a result of the time differences no matter how you've travelled.

Where these flat-beds excel is for the overnight flight back from the US. If you have the discipline to ignore the movies and the wine, you can get a crucial five or six hours sleep lying flat. Should you have a vital meeting at which you need to be at your best, this might be the solution.

But of course, even then, you've still got to get there once you get off the plane. Squeeze yourself on to the narrow escalator. Wait at the station. A sweaty, clattering ride into London. The streets dark and damp...

Eos Airlines: 0800 019 6468; www.eosairlines.com