We had a great time staying in Nina's apartment. We weren't home a lot (we crammed a lot of sightseeing in to 6 days!) but it was perfect to have our own area of the house to retreat to after full on days, and not have to worry about disturbing anyone.
The apartment itself is set off of the road at the back of a small courtyard so whole you just have to walk out onto the street and you're in the thick of the buzzing Bastille neighbourhood with countless bars and restaurants, the apartment is still very secure and quiet.
Although unfortunately we didn't get a chance to spend too much time with Nina the brief chats we had were very nice and she had some great suggestions for us in term of eating out and transport etc.
We would definitely come back to stay!