We stayed with our friends (two 7 year old kids and 4 adults) for one week in october. It's located in a very good place, 5 minutes walk to the metro station line 8, lots of cafe and markets nearby and it seems to be a safe area. We didn't have any problems about heating. Flat has everything you need and we were comfortable.
Saturday nights can be a little noisy in the front rooms because of the cafe in the building across. And the location of bathroom required some additional coordination among us.
We definitely should go there again in our next stay in Paris.