We stayed in this appartment for a week and we loved it. At first it might seem too small but with all that there's to do in Athens you'll be using it almost exclusively to sleep and take showers.
The location is the greatest advantage of this room, everything is at a 10 min-walk distance. After a couple of days we couldn't imagine staying anywhere else, as we were able to come back for quick naps after lunch to get more energy for our afternoon activities and that was only possible because of the location of the appartment.
The AC and the TV with netflix and youtube were a blessing after spending the whole day walking under the sun at over 30C.
Christos was very friendly and he was always very helpful and attentive to our needs.
It might be true that for people with very light sleep the noise can be a problem, so we brought earplugs in advance which we didn't get to use because we would be totally exhausted after all the walking, the noise was not a problem at all.