(CNN) -- Few airline routes are as cutthroat as the one between London and New York.
It is the world's busiest intercontinental route and -- peppered with business travelers -- one of the most lucrative. There are few lengths airlines won't go to in the hopes of getting a piece of the action.
We look at how the different carriers stack up.
BA: It's all business (class)
It may not be the cheapest way to travel between the two cities, but British Airways' all-business class flight is definitely one of the plushest. Aimed at London's and New York's bankers, it is also one of the few flights to leave from London City Airport.
Perks include all the standard business class amenities -- gourmet food, lie-flat beds, airport lounge access -- as well as some innovative extras. Instead of a traditional in-flight entertainment system, for instance, customers are given use of their very own iPad.
Perhaps the sweetest offering, however, is that passengers get to skip the line at customs. To facilitate this, the plane makes a pit stop at Ireland's Shannon Airport, which introduced a pre-clearance facility in 2009.
It helps that BA has partnered with American Airlines. Together, the two carriers own the largest market share (53%) of this route, and offer the most flights -- 17 a day -- between the two cities.
Delta-Virgin: When in doubt, merge
Last year, neither Delta Airlines nor Virgin Atlantic held a particularly admirable market share of the London-New York route. Then, they decided to merge, with Delta acquiring 49% of the British carrier. For Delta, the move meant the ability to offer three times as many flights between the two hubs. For Virgin, it meant access to new, untapped markets in the U.S.
"We are a UK-based airline, and we need to offer a set of flights and services and attractive features to customers in the UK first and foremost," admits Craig Kreeger, CEO of Virgin Atlantic.
"We need to expand our network in order to do so, and Delta helps us going in one direction -- but it is the direction that is the biggest for us."
Since the merger, the airlines have acquired 33% of the market on that route. Still, the two airlines have retained their separate identity, with separate perks. For Delta's U.S.-bound Diamond Medallion customers (the frequent, frequent flyers who cover at least 125,000 miles per year), a Porsche will transfer them between gates.
Lie-flat beds and gourmet food (with wine pairings) are par for the course on business class flights, though Delta stands out by also providing Westin Heavenly in-flight bedding. Delta also offers the Dine & Rest program, an expedited meal that lets flyers chill out for the remainder of their journey.
Younger road warriors traveling in business class, meanwhile, are drawn to Virgin's cool lighting, on-board bar and limousine pick-up service. The London Heathrow Clubhouse -- Virgin's upper class lounge -- meanwhile excels at offering the unexpected, including free-flowing cocktails, and restaurant-quality meals. There is even a spa to help visitors unwind before a flight.
United Airlines: The underdog
United Airlines, which merged with Continental Airlines in 2010, can't hope to compete with the other industry giants, who have invested a lot of time and money on the New York-London route.
Though they offer the fewest daily flights (five), the carrier has made inroads. United has set up a plush hub in Heathrow's newly renovated Terminal 2. On the New York-end, they fly into Newark, which offers smaller queues than JFK Airport. Jeff Smisek, United's CEO, also says the airline is working with its strengths.
"Our position is basically that we offer a good service out of New York. It's not as big as BA's, but we offer a good schedule and we offer our entire network with a lot of connecting opportunities," he says.