Insik's place is awesome! I have stayed at many AirBnB locations around the world for both work and family trips and this is the best experience I have ever had. The location is an easy 10min walk from the Shinbashi Station, from which it's quite easy to take JR train or the metro subway lines to explore rest of the city. The biggest train hub of Tokyo Station is only 2-stops away.
Insik was incredibly diligent and made us felt like welcomed guests throughout our whole stay. Starting with the check-in, he let us stored our luggage in the apartment even though we were early and the place still needed to be cleaned. When we returned later for the check-in, he provided a detailed description of all of the amenities. For our family of 4, the most unbelievable feature was the 2x bathroom and 2x showers. For such a studio apartment, I do not believe it is likely to find this anywhere else. The rest of the place had many small, thoughtful details which made the experience much more enjoyable than simply sleeping for a few nights.
I highly recommend this place if you want a great base from which to explore Tokyo! I would certainly consider coming back again next time.