Legacy carriers like Delta and American airlines offer similar products with names like “Comfort+” and “Main Cabin Extra.” Younger airlines like JetBlue are in on the legroom game, too. Their “Even More Space” seating even adds early boarding to the upgrade.

These seats shouldn’t be confused with “premium economy” — an actual class of service that, for now, is only offered by a growing number of international carriers. Earlier this year, Singapore Airlines launched its service for long-haul routes in between regular economy and business-class cabins, offering seats that are wider and feature leg rests, larger TV screens and enhanced meal service. Because you’re moving to a dedicated class of service, you could be paying hundreds of dollars more but it’s more of a pure “upgrade” at a lower price than Business or First Class. For instance, a sample one-way fare on British Airways on Christmas Eve between New York and London shows a fare in premium economy that costs $571 more than coach, but is $5, 414 less expensive than a business class seat.

U.S. airlines have been slow to catch on, but American Airlines in December announced the installation of true Premium Economy seating aboard international flights starting in 2016. Seats will be wider, offer significant additional width and legroom, fancier meals and larger personal TV’s. There are no immediate signs that other legacy U.S. carriers will follow suit, but while American paves the way, it will be interesting to see if and how long others will wait before they follow.

For now, U.S. flyers will need to settle for extra legroom without better meals or the extra wiggle room for their hips. As a blogger, I review airline seats. So I’m the type of flyer who doesn’t mind connecting four times to get to a destination just to take in the experience of flying. But just because I love flying doesn’t mean I don’t like to do it comfortably. In fact, it’s the reason I only review seats that are, in some way, upgrades.

So here’s a cheat sheet listing 4 affordable upgrades offered by the four major U.S carriers:

• United Airlines “Economy Plus” is the birth parent of the most modern version of extra legroom seating, and frankly, the most bare-boned. If you want extra perks like early boarding or a generous pour of boxed Pinot Grigio, it’ll cost you extra. Food and drink service is the same as in economy, luckily United has just reintroduced free snacks to everyone on board.

• Delta’s (DAL) “Comfort+” is actually doing well to bring value to their version of this upgrade. Comfort+ adds Sky Priority early boarding, free drinks, premium snacks and complimentary in-flight entertainment.

• JetBlue’s (JBLU) “Even More Space” adds early boarding to their leg-friendly seating. What’s missing on paper are “premium” snacks, but the airline already offers a fairly robust snack offering to all of coach. On certain aircraft, in fact, there’s a self-serve snack station with a variety of munchies and cold drinks. “Main Cabin Extra” is what you’ll have to settle for until American Airlines starts introducing their full premium economy seating on international routes. Similar to JetBlue, you’ll get earlier boarding but snacks are limited.

Because the larger airlines have diverse fleets, the amount of added legroom that come with these seats can vary widely. With legroom, the only common feature of these mini-cabins, we’re not sure there’s value here for everyone that’s not at least fairly tall or claustrophobic. Food and drink can be a factor in some of the choices we’ve covered but it’s worth it to consider how much you’d pay a-la-carte for those tiny bottles before you pay too much for space you don’t want or need.

Jake Redman is founder of ModHop.com, which helps flyers find the perfect airplane seat. He also produces and hosts shows on SiriusXM Radio. This article originally appeared in ModHop.com.