Regrettably enough, my family was not able to spend much time in Armelle's place. However, the experience there was great. Parents and 2 teens didn't have any problem in staying there. Wonderful location, too. Lots of nearby cafes to enjoy real Paris.
If you plan to stay there in mid summer, however, should keep in mind that the duplex doesn't have an air conditioner. I don't think it matters usually and the ventilation was spotless. But the city was terribly hot when I was there. Other than that, excellent experience!!!