We stayed at this hotel overnight enroute to Europe with Japan Airlines in December. Fortunately the accommodation was paid for by the airline, otherwise we would have been very dissatisfied with this hotel, even if their tariff was cheap.
Despite requesting a non-smoking room the first room we were given was impossibly smokey.To the hotel's credit we were given another room, however this room was very small and badly in need of a comprehensive upgrade. The carpet was old and worn and the curtains and bedspread were very old and desperatley in need of laundering. We were told the air conditioning had been turned off because it was winter, so we had to open a window to get some fresh air.
We have previously stayed at Hotel Nikko at Narita Airport and would consider it to be a far superior option to the Marroad Hotel.
If you do choose to stay at the hotel provided by Japan Airlines then be prepared for a very basic hotel.

This is an excellent large hotel near Narita Airport.
I had a good view of airport runway from my 10th floor soundproof room. Room was a good size for a single compared to say Shinjuku or other Tokyo hotel.
Choice of eating locations within hotel. Excellent cafe on ground floor (lobby).
Very good well stocked convenience store on ground floor near elevators.
Business centre and a couple of internet terminals for 100yen.
WiFi may vary with the location within hotel. Usually best near conference rooms.
Very good choice hot and cold buffet breakfast on the 13th floor with views of early aircraft arrivals.
Free and regular shuttles to airport T1 & T2. Easy to connect to various trains to Tokyo or Yokohama or .....
Free regular shuttles to Narita City shopping centre. Excellent supermarket and numerous food cafes with plenty of choice.
Great location for business or conference on the Narita area.
Recommend it and will stay again.

We were stuck in Narita for a night waiting for our flight the following afternoon and decided on the Marroad due its economical perks (ie. cheap!).

The place looks nice enough from outside and in the lobby. The gym is a total dump, only had up to 9kg in weights, a huge empty space with one broken treadmil and stains on their far too old carpeted floor. The mens' lounge was a furnace. pool and hot tub were nice. the signage to the pool could use some ammending with proper english translation...hahah for example something along the lines of, "please do not share gargle with the other patients" and so forth.

Oh and every room smelt like mould...and the 12th floor is some bizzare abandoned limbo with swinging light bulbs...yech.

This is a place to sleep and nothing else. Can't be beat for the price. You will get a small but completely adequate room that is clean, well ventilated and airconditioned, and usually quiet (unless they put you in the part of the building that is right above the rail tracks - to be avoided!). In winter the aircon is disabled and it can get warm in the room but you can open the window to cool it out. As the airport closes around 23:00, it's quiet at night. Other than that, not much going on. No Internet on the room and no room service. The food at the restaurant is not great but edible. There is a convenience store now which will supply you with the basics but better bring your own food or eat at the airport. Getting around isn't that easy. You can call a taxi but with the language issues most people will be confined to the hotel. Service at the hotel is minimalist. The gym is a poor joke. But again, what do you expect at the price? On the other hand, two weeks' free parking which is a big deal around here. Popular with budget travellers from Taiwan in particular. For a more upmarket, full-service and much pricier alternative, the Hilton is a good choice.