I stayed for an entire month in Zaklina's apartment. Very positive experience. The house was sparkling clean. Obviously rennovated and ideal for a couple. Big, king size bed with comfortable mattress. Equipped with everything i needed for my long term stay, so i can imagine there should be more than enough to accomodate shorter stays as well. Kitchen was equipped with a modern fridge and washing machine which i used extensively. Nice, rennovated bathroom.
During my stay, outside temperatures reached 45 degrees, so i didn't fully enjoy the really spacious terrace/balcony. At least the new AC system was powerful enough to keep me cool inside.
Lots of clean extra clean towels and bed linen. Big television with Netflix.
Check-in was outstanding, as was checkout and communication in general. No complaints with the neighbours as well.
5 mins to the metro station.
Finally, in order to be fully objective i need to mention the area: Filis road is known to be a somewhat deprived area to live. But i lived there for a month and never felt in danger. Used to bump into many foreign tourists in the supermarket (next door to the flat) and the surrounding roads.
All in all, i would stay again when in Athens.