Location is great. This is a good, inexpensive option if you are just crashing for a short period of time. Easy to get to/from the airport, a very short walk to the Eiffel Tower and other attractions, grocery stores and restaurants within a couple of blocks.
I did not interact much with Leo (I dropped my bag, took off and then came back to sleep a few hours before catching a very early flight) but I can tell he seems to be a genuinely nice person and interesting to chat with. You must know you will not have independent access to his place, that is you won't get a key (I think this should be clearer in the listing). The experience is more like staying at your friend's dorm on campus. I had no trouble with this since I am pretty flexible and accommodating. If you are too and all are in town just for a few hours, this is a good option.