The appeal of not shelling out the big bucks for business class or getting crammed into a tiny seat in coach gave rise to a class of service that would bridge the gap and became known as premium economy.

My first introduction to the premium economy class of travel was on a Virgin Atlantic flight from Los Angeles to London in 2000. Though I was unaware of it at the time, both Virgin Atlantic and EVA Air featured this service on select flights since 1992. The two carriers were pioneers in designing a class of service that would upgrade the space and service of economy class but be more reasonably priced than business, albeit nowhere near as cushy.

When it appeared the public liked the benefits of a little more comfort without a hefty price, other airlines jumped on board, starting with British Airways. Today, many carriers offer this class of service, especially on long-haul flights, and more are hopping on the bandwagon every year. Singapore Airlines, Lufthansa and Air Canada will offer premium economy on at least some of their flights in 2014 and 2015.

In May of this year, Singapore Airlines’ chief executive, Goh Choon Phong, announced the airline would introduce premium economy class beginning in the second half of 2015.

Lufthansa plans to offer its in-between class by this November. “Our premium economy class will create a completely new travel experience that combines affordability with greater comfort,” says Jens Bischof, CCO and member of the Lufthansa German Airlines Board in charge of sales, product and marketing.

Air Canada announced the newest addition to its fleet, the Boeing 787 Dreamliner, will offer premium-economy service. According to airline executives, the service will include seven inches more legroom, two free checked bags, upgraded meals and priority check-in and boarding.

On the other hand, Gulf carriers Emirates, Etihad Airways and Qatar Airways have no immediate plans to add a premium economy class of service. They prefer to focus on the higher-end cabins, maintaining their economy classes already provide a “premium” experience.

As to whether the perks justify the price, it depends on who you ask. Journalist, author and TV correspondent Kimberly Button says, “I’ve flown premium economy class on Virgin Atlantic and United and highly, highly recommend it. Yes, it is an up-charge for getting what was part of your normal ticket price just five years ago, but it does make sense.”

However, award-winning travel writer and photographer Yvette Cardozo sees it differently: “I’ve flown premium economy on several airlines, and while I think it’s yet another ploy by the airlines, it’s often absolutely necessary if you want to arrive with knees, back and camera gear intact.”

China Airlines’ premium-economy seats © China Airlines

Among the airlines adding the in-between cabin is China Airlines, debuting a premium economy cabin in December 2014 on the Boeing 777-300ER. The fixed backshell and front-sliding seat offer recline with no disruption to other passengers. Each seat is equipped with power outlets, USB ports, personal reading lights, storage compartments and comfortable leg rests with two-position foot pedals. The industry-leading 12.1-inch touchscreen screens at every seat feature Seat Chat, a unique social chat function for sharing movies, music and messaging with other passengers.

Not all premium economy classes are created equal, but the one constant is five to seven inches more legroom than coach. Some airlines offer one to two additional inches in seat width, upgraded food, larger video screens, adjustable headrests, leg rests or lumbar support, laptop power ports and even amenity kits.

Probably the biggest reason travelers choose premium economy is the extra legroom, so it’s little wonder Air New Zealand won the award for the World’s Best Premium Economy Class Airline Seats for the second year in a row at the 2014 World Airline Awards. The seat pitch on its larger aircraft is three to four inches more than its competitors’. In addition, the service includes premium check-in, complimentary amenity kits, premium headphones and priority baggage upon arrival.

Is flying premium economy economically sound? It depends. How much extra you pay over the economy price varies from airline to airline but also differs according to how far in advance you book and what special deals the airline offers at the time you book.

SeatGuru established a general rule of thumb: If you book in advance, premium economy is generally about 85 percent more expensive than economy, while closer to your departure it’s only 35 percent more expensive. I decided to try out this theory. I booked a flight on British Airlines’ premium economy class (World Traveller Plus) one month in advance at a cost of about 30 percent more than the economy price. Then I booked on British Airways’ premium economy class four months in advance, and the cost was almost double the economy price.

Certainly, determining if premium economy is worth the extra cost is a personal decision, but I look at it this way: If the flight is more than 10 hours and the extra tariff will be less than 35 percent above the economy price — and I can be guaranteed a window seat — I’ll probably go for it. And always ask at the check-in counter about any available discounted upgrades. You might get lucky.

Premium Economy chart