Had a pleasant stay there!
The hotel is in a nice and quiet area, but since Hatagaya Station is less than 2 minutes away Shinjuku and Shibuya can be reached in very short time. Also multiple restaurants and two convenience stores can be reached in less than 2 minutes of walking.
The rooms were very tidy and were cleaned daily. We went to Tokyo in August, with outside temperatures rarely below 28C, but were delighted to find that every room is equipped with an AC. The rooms are quite small, but since you will likely only sleep and have a shower in there this is not really an issue.
Breakfast was served from 4am until 11am, and the buffet included various jams, toast as well as small buns, and daily changing sort of juice. Admittedly not the biggest choice imaginable, but definitely sufficient for a breakfast.
All staff members were very friendly and helpful, and even greeted us nicely at check-in, despite the clock showing quarter past midnight.
Overall we had a pleasant stay and were positively surprised given the hotels price-point.