We stayed at the Sunroute Plaza for two nights as we were passing through Tokyo. We took Narita Express from the airport, which was very simple. The hotel is just a few blocks away. The hotel staff were extremely helpful and polite and spoke good English, including the wait staff in the restaurant.

Our room was very clean (small by US standards, but that is to be expected) and our bed was quite comfortable. Shinjuku station is a few blocks away, so we used the train several times, which was very easy to navigate. The nearby area has a lot of restaurants and interesting things to see, so we walked around a good amount as well.

The only real asset of this hotel is its great location, right beside Shinjuku station.
We were possibly very unlucky with the room we were assigned to. Air-conditioning was poor. Each night the heating system would turn off by itself and when it was working it was loud and the air coming out was cold. Even though we complained and each time someone came up to check the heating (they even changed filters inside of the air-conditioner), situation hasn't changed for the whole duration of our stay in the hotel.
Room was clean yet the walls were dirty. Toilet was Ok yet it had an odd smell.
On the other hand, staff was friendly and tried to help each time, though unsuccessfully.
There is a possibility that we haven't been lucky with the room and that other rooms are in better condition...however, all in all, we would NOT recommend this hotel.

Every time my family and I travel to Tokyo we stay here. It's easy and convenient with airport limousines buses stopping right at the door to and from Narita airport for only ¥3000. No need to drag your luggage up and down escalators to catch the skylines which is only ¥600 cheaper.
It's close to the main and busiest train station in Tokyo with JR and metro lines to travel to all tourist locations. There are fantastic restaurants and shops such as Lumier shopping centers and Tokyu hands just 5 minute walk away. Also if you're a member of the sunroute club check out is at 1pm! Great size rooms for tokyo standards, friendly staff and clean.

Location was convenient, nice and close to the station. Rooms were small, even by Japanese standard. Hotel could use a clean. Carpets were quite dirty and walls had lots of marks. The internet connection was unreliable, lots of dropouts on ethernet.
Found the breakfast average.