We enjoyed our stay at Kyoko's house as 2 couples traveling together. She was easy to communicate with and fast to respond, although we had no reason to contact her as seemingly every detail of locating the apartment, checking in, and staying in Tokyo were clearly thought through in great detail in order to make everything very easy and seamless.
We were attracted to this listing primarily for the neighborhood/location and for the spacious layout. Although many Airbnbs in Tokyo seemed to cram beds in every available space, we liked that Kyoko's house had a sizable common area (essentially the whole second floor) where we could gather and relax together. The house is definitely set up for travelers, with numbered bedrooms and many informative info packets, and could easily comfortably accommodate a group much larger that ours. The only minor drawback (and for some people it is perhaps a positive point) is that there are perfumed air fresheners sprinkled throughout the house and the scents felt rather overpowering, though this is something that I have a particular sensitivity to.
Our aim was to stay in a hip walkable neighborhood close to transportation that was a bit set apart from the throbbing churn of the city center, and Shimokitazawa delivered on this. Although the actual block where the house was located is pin-drop-quiet residential (almost a suburban feel), the more lively streets with great shops/bars/coffee/etc are immediately nearby. If you are looking to do some advance research on the area, the Airbnb site has a neighborhood guide that gives a bit of the flavor. We also enjoyed the book "Tokyo Precincts: A Curated Guide to the City's Best Shops, Eateries, Bars and Other Hangouts" that has a great chapter on Shimokitazawa and outlines a few specific spots.

Although the closest metro station (Shin-Daita) is just a 2-minute walk away, we found that for most of our outings we used the Odaku line at the Shimo-kitazawa station, which is more like a 10 minute walk. Being urban-dwellers (NY and SF), these both felt like they were within totally normal short distances, and the walk to either station felt perfectly safe whether in daytime or night.