Positives: The room is clean and well-organized. Air-conditioner works well. Bed is comfortable. Fridge good for keeping drinks chilled. Laundry room on ground floor. Simple self-check-in process. Portable wifi router very helpful when exploring the city. Location about 10 minutes' walk from Ikebukuro station. Lots of restaurants and convenience stores nearby. Seibu and Tobu department stores at the station, so lots of shopping available.
Negatives: no microwave (ask the convenience store clerk to heat up the food), no blackout curtains (sun rises at 4.30am in summer), and cigarette smell in the carpeted hallway (the room itself is fine). Overall I had a good stay, but if you want to sleep in, please check with the host first regarding the curtains.