Space seems bigger in the photos. It's a nice walk to and from Nakano Fjimicho Station with a Family Mart, 711, a huge grocery and a Daiso along the way. Eat at the Japanese diner across the street from the Tokyo Metro exit (and get the ginger pork set meal, it's TDF!!!!).
It's the extra transfer/interchange to the Honancho extension on the Marunouchi Line that's off-putting especially when you're exhausted from all the day's walking and shopping, carrying heavy shopping bags and you just couldn't wait to get home.
But overall, it's a nice quiet neighbourhood (with paper thin walls). Comfortably fits 4-5 people.
It's a plus that the place has two bathrooms. Saves time in the morning.