Just getting this out there: the washroom is super-tight. If you're a larger person (height or girth), this will be a problem. The building is a bit on the louder side with many guests overall.
However, it's a very good value and is located incredibly close to a metro station which is a mere two stops from Shinjuku Station. It's located on a market street, so food and drink as well as restaurants are, literally, out the door and down the street. If you merely need to rest up, there is a full bed here offering comfortable sleeping for two people and is a good choice for exploring the rest of Tokyo.