The location is great, in the middle of Roppongi, near the subway station to be able to move around Tokyo.
Like all of Japan, the area is very safe, near shibua and shinjuku are.
Kentaro & Kioko are very friendly, they give you all the necessary information and assistance so you can enjoy Tokyo.
The apartment is very comfortable, you have all the necessary accessories (washing machine, microwave, wifi, etc).
When I return to Tokyo, I will undoubtedly return to the Kentaro & Kioko department.