United Airlines launched a new series of international business class seats last week as part of its Polaris premium experience overhaul.

Officially kicked off in June of last year, segments of the Polaris experience have actually been trickling out ever since, but only now are flights actually operating with the updated seats. In December, the first Polaris lounge opened up in Chicago while updated amenities such as blankets, pajamas and retooled menus also started appearing on aircraft.

Early last week, United opened up its first upgraded aircraft, a Boeing 777-300ER, for a media preview from Chicago to San Francisco. Later in the week, regular service started operating between Newark and San Francisco.

Reaction from the media and customers has generally been positive. “Kudos to @united on the new 777-300ER Polaris launch.” tweeted Dave Tempkin, the VP of Global Networks at Netflix, adding that he was “quite pleased with the new seat.”

Other feedback has been more measured. Henry Harteveldt, an airline, hotel and travel industry analyst, lauded the design and the details but pointed out that the new seats were slightly narrower than competing products on American and Delta.

These comments followed a familiarization trip United offered airline industry observers.

Polaris seats represent an important step in United’s goal to better compete with both legacy and international carriers. Each Polaris seat has the ability to lie flat and has direct aisle access, two features that are now common among leading international premium cabins. Additionally, the airline is putting extra work into the Polaris soft product, from dedicated airport lounges to over-the-top in-flight amenities. The cabins are a major improvement over the airline’s current international business class offering, which in many cases offers four seats across in business class.

As crews and passengers get used to the full Polaris experience, United plans to continue flying the 777-300 widebody on the domestic route between Newark and San Francisco. On March 25th, service will expand internationally to routes from San Francisco to a variety of ports in Asia.

Photo Credit: A Polaris-class seat on United. The company recently launched the in-cabin portion of the product. United Airlines