Book it now -- finish reading this after!
This apartment is fantastic. The balcony is a great place to sit and relax with a glass of wine when your feet are tired from running around Athens all day. And the VIEW! Amazing. You can see the whole city. The Acropolis is blocked from certain angles by a building next door with a pole sticking out of the top of it. But, that's hardly a complaint. Centrally located and close the the metro. With the exception of the airport, it didn't take my girlfriend and I more than about 20 minutes to get pretty much anywhere we wanted to go.
There was one issue with water leaking from the tub/shower. We told them about it and they offered to fix it immediately. We weren't bothered by it, we declined... it was more of a heads up for them. But that was the only thing even remotely unpleasant about our stay. They were super communicative, let us check in early... the apartment was modern and comfortable and had everything we needed for our stay. I would highly recommend staying there and I would happily stay there again.