You can't beat the location! Literally across the Louvre through a bridge, and you can walk to so many main tourist spots: pont des arts, notre dame, musee d'orsay, the latin quarter, arc de triomphe. And after a loooong day, the neighborhood feels very safe to come home to at midnight. The twinkling lights of eiffel were a nice view at bedtime, just before we closed our eyes.
We didn't meet Hiroko, but that was our own fault, we got a lil lost from the metro to the apartment, and she had to go, but she left a very nice note and called us to check that we were OK. She is a very nice host and responded quickly with every message.
Overall, I would recommend this apartment to siblings or a young couple, because there are maaany steps to climb and the WC makes it a bit awkward to friends.