Kimie's place is in a quiet neighborhood, with a super cute quiche and tart place next door and a great coffee (Good Jones) shop a few doors down. Be sure to watch the video directions she sends and take screenshots before you lose wifi, otherwise you might get lost in the rain like I did! It's definitely not Shinjuku though, but Iidabashi. We found it easy to get around via train, but note that it's not walking distance from the Shinjuku/Shibuya action. The heated Toto toilet is nice! And the tub, like most Japanese apartments, is small so be careful if you're tall. No bathroom sink, only a kitchen sink, but again that seems to be fairly common in small Tokyo apartments.
Overall, our stay was great and the host was very communicative and helpful.