This place is awesome! We had a four day trip to Berlin with friends. In total, three occupants. We had such a good time and the apartment was the perfect size for us! It would also work really well for two couples.
The location in Friedrichshain is awesome! There are so many restaurants, nice bars and little shops around and everything is affordable! You can get great breakfast at the cafés one or two blocks away. Also the Ostkreutz S-Bahn station is a short walk away. You can also take light rail.
The apartment itself is really nice! The two balconies are great for socializing in the evening. The rooms are seriously tall! Like 5 meter. Love it! :) Comfortable beds, nice roomy bathroom and a nice kitchen.
If you like Friedrichshain, you should definitely consider this place!