Stayed here for 3 months with my family. This is one of those places that just works. Big, functional, and having 2 balconies is pretty sweet. The internet isn't great, but it is the best you can get in the heart of the city. The closer you are to the Acropolis, the crapier the internet gets. It's an Athens thing, I guess. AC is good, but doesn't reach the kitchen, or the main sitting room. Loads of fans and even in 47 degree heat, it is fine.
The location is spectacular. Close to all the attractions, metro and buses right there, and the restaurants! So many, and all of them amazing.
Out the door to the left is the best coffee shop I've found. Out and to the right is Kalamaki. Exceptional food. An 8 minute walk is Romatella. Best pizza you'll have, and also go to Django. Literally the best ice cream in the world.
Overall, a great stay. Athens is a treasure, and this apartment is an excellent base from which to explore.