In short, this place is a nice price while having everything you need. The bed is pretty big and comfortable, and the dividers make it private as well.
What I want to mention specifically is the location. The closest station, Sumiyoshi, is a <10 minute walk away and has two Toei subway lines, allowing you to go to many different stations in Tokyo without taking much time. There is not only the 7-Eleven next door, but also a number of restaurants (yakitori, ramen, chinese, etc.) as well as a supermarket on the way to Sumiyoshi station. The supermarket has a nice selection of food products as well, so keep that in mind. Also, not too far away there is a shotengai (basically a bunch of stores on the same long road) called Sunamachi Ginza Shotengai that has a lot of cheap and good street food. If interested, be sure to watch some videos about it on YouTube and plan to go there when you have a bit of time.