We (2 persons) stayed 8 nights at this place, and we enjoyed it quite a lot! We got it at quite a fair price too for Tokyo so that was a nice bonus.
It is very easy to find, the instructions are clear and the host answers quickly. We did not try to cook but the rest of the appliances worked perfectly fine. If you are interested into cooking at home, please note that there was no cutlery of any kind. Convenience stores will provide you with chopsticks and spoons accordingly to your purchases though.
Beds were great, the AC was a savior for us (it was quite hot). Note that the building is located near a train track cutting the road, so expect ringing noises and trains up to midnight. My sister had no trouble with it, and some earplugs were perfect for me to sleep soundly.
The location was really great for us! The Oyama station is really close, and you just need three stops to get to Ikebukuro, from which you can get all the lines to travel around Tokyo. Perfect fit for us!
All in all a great stay for us, I would recommend it for people who are okay with being a bit outside of the center of Tokyo!