Short version: I can recommend the place for up to 5 days stay with maximum 3 people. You get a good deal.
Long version:
The location is very close to the JR ring line and a perfect place to start all your adventures in Tokyo.
We lived here for 5 days with 3 friends and had just enough space to stay comfortable. I would not suggest to bring more people than 3.
The bed was comfy and the Futon as well. The sofa was not prepared so we had to improvise during the first night. I suggest you make sure the host will prepare it for sleeping in case you need it. one more remark here. the sofa is good for one person but definitively not two!
The kitchen was equipped with a water cooker and some cups, bit not more. In case you want to cook on your own, that's not the place to be.
We enjoyed the stay here and will book again for our next trip.