We (a family of 4 with 2 teenage boys) spent 3 nights here and would recommend it. It is quiet, central (we both walked and took metro to central Athens and both were convenient) and has everything you need. But it's the rooftop garden that make this apt so special - a real oasis from the big city.
If you are a runner, then the park around the hill of Likavittous is a great place to run. From the apt to the top it takes about 20 min to run...if you go early (before 7) it is cool and you have the whole hill and views over Athens incl Acropolis to your self!
we would also highly recommend the restaurant Nice n Easy on Omirou in Kolonaki (about 15 min walk).