The location is awesome!! The view is wonderful!! It's literally just steps from the Acropolis, the Museum, the Metro, and plenty of great dining. The apartment is beautiful and comfortable. It's been renovated and feels like a very upscale hotel with the nice finishes, and the thoughtful touches of bath products, snacks, etc. 2nd bath is a little small, and showering in there, while possible, was not something we tried to do.
If you have a car, especially a larger one like we did, parking can and will be a challenge as the apartment is located on a pedestrian way (though you can drive on it temporarily to unload), but surrounding streets that you can park on are very crowded with parked cars. It took me close to 30 min to find a spot a 10 min walk away that could hold our 9 passenger van, though I did pass a few smaller spots while looking. Konstantinos recommended a couple of parking garages but they wouldn't accept the van due to the size. We left the van in the spot for the duration of our visit so as not to lose the spot, but the metro is so close, it wasn't an issue for us transportation wise.
All in all, it's a 5 star place and as long as you don't need to park and re-park daily, I'm not sure you'll find a better place to stay if you want to be in the heart of Athens. Our family of 4 (2 adult daughters) loved it.