This was a very conveniently located apartment. It was a ~10 min walk from the Acropolis metro station if you are coming from the airport. We were met outside the door and shown inside. Our host was very informative of the area and gave some good suggestions for less expensive meals right near the apartment that saved plenty of euros vs. in plaka. We were within 10-15 minute walk of any of the attractions we wanted to see - plaka, acropolis, panathenaic stadium, etc. Great location that is just outside of the intense crowds of Plaka.
There is a busy/loud intersection just underneath, but i am not sure it would be much different many other places in that proximity to Plaka. Large shower compared to rest of our Greece trip which we appreciated, and a nice balcony as well. I would recommend for first time travelers to Athens to get a good feel of the old city without being overwhelmed.