The place is nice, clean and cozy, located in a very quiet neighborhood. About 5 minutes walk to the nearest metro station, and about 10 minutes walk to the Okachimachi station of JR Yamanote line.
It's like full self-help service, you can do almost everything according to the guide manual you've got. But the staff is still very helpful since they have a 24 hour hotline and there are 4 languages to choose.
The only downside for me is that there's no elevator in the building, and the stairs are quite narrow. I was traveling with a baby and lots of luggage, so I had to leave the big suitcases and the baby stroller in the lobby every night. The warm part is that the suitcase storage facility in the lobby is very easy to use, and no one touches others' stuff during the stay. I'm not complaining this because I knew the fact before I made the reservation, just to let people who'd like to shop a lot get prepared for the case.
Overall it's a very nice place to stay, and I'd like to come again if I could travel lighter next time.