Very easy check in on arrival. Location is perfect, within walking distance of many sites and great for dining out options in the 6th.
We had a 7 and 10 year old with us, so 4 of us and was perfect for us. Bigger than a hotel room in Paris and comfortable.
Apartment needs a bit of TLC. A lot of damp issues, shower wall disintegrating, windows wet in the mornings. But all in all clean and as per the pictures.
As with most of Paris there is road/traffic noise at night and the usual sirens. I would definitely recommend but for their own sake I would do repairs and damp proofing before it gets worse.