It is a great place to stay, the location, level of noise from outside, proximity to shops, bars, transport stations, sightseeing - is good. We were 4 in this apartment and feel good, but for 8 people it might feel crowded, but if you are planning only to sleep there then it should be ok. Anyway, it's the old part of Paris and it would be naive to expect wide corridors and big halls like in Palace =)
Owners responded to all our messages quickly and in an informative manner. All instructions were very clear and we had no issues getting keys, for instance.
Overall, nothing makes us sad during a visit and we got very positive vibes from our trip in Paris.