We loved our experience here with two young kids (1 and 3 years old). The apartment is a short walk (9 minutes or so) from two subway stations, two grocery stores, a drug store (diapers), and a 7-11 (foreign-freindly ATM). The building even has an easy-to-remember name on google maps, so finding your way back is easier. The combo washer-dryer works very well, so pack lighter than you would otherwise. The network was fast and reliable, and the host even included a pocket access point, so we had a hotspot in our backpack for our whole stay.

There is also a playground a couple of minutes down the street that our 3-year-old fell in love with on first sight.

The only odd bits are that the doors a little short for people over 6-foot (this seems common in Japan), and the kitchen faucet shuts off by moving the handle up (does not seem common in Japan... drove me a little nuts).