Christophe's place is a lovely little studio and he and his partner were really helpful! The internet and faculties are great, it has everything you need for a couple of days in Paris.
One thing to note - we arrived at night and were quite intimidated by the amount of homeless people sleeping outside the entrance to the building. We almost had to step over them to get into the door, and we definitely stepped over a few when we left at 5am early to get to the airport. They didn't harass or call out to us at all, but I think it's important to know before you stay here!
The location is quite central however it's still a 20-30 min metro ride to the Eiffel Tower for example, but the metro is nearby and very convenient.