The apartment is good for just one night. It has excellent WiFi, you can travel into the city easily, you have a LIDL for shopping and several bars in the street.
However, two or more nights really is a stretch. The beds are really hard and uncomfortable, which doesn't lead to a sound night. The room was pretty small, the fridge was noisy (the walls are thick, though, didn't hear anything from the neighbouring children), the bath was not cleaned, even though it was used by several groups on a daily basis and my friend mentioned a strange smell each time she stepped into the room after our trips.
The Check-In was confusing, which could easily have been avoided would Frank or Nikol would have answered any of my messages in the 5 months between my booking and my actual stay, which was not comforting in any way and led to some troubles with the Check-In. I do have to complement their quickness in response, however. As I called them, as we were not able to check-in due to the mentioned troubles, they gave me another way in.
After all, it was ok. It's a cheap accommondation and was fine for the first night, but I would not book it for a second stay, especially if I travel with a group again.