Great location, easy walking distance (20 minutes or so) to the Acropolis and Hadrian's arch. a bit further gets you to the ancient agora, roman agora and Hadrian's library.
The flat itself has 2 bathrooms, although one is *very* small so for the most part we used the larger one. The ceilings are high and the flat is very spacious and nicely furnished. At night the balcony doors in one bedroom can sometimes blow open, but we just put our luggage against it and it was fine.
The internet speeds are quite slow, particularly upload so posting photos/cloud backup was a bit painful but manageable.
Overall it was a very nice flat with groceries and restaurants right across the street. Would definitely stay again.