Room is very small, but efficient. It is officially the smallest shower I've ever used. The shower/toilet/sink is all one unit (with a shower curtain). I'm 5'7" and 140 lbs, not a big guy, and it was very tight having a shower, just FYI.
No elevator and I was on the 6th floor. I'm in decent shape, but if you start sweating by just looking at stairs, I'd avoid this place.
Neighbourhood was a bit dirty, but I didn't feel unsafe, even late at night.
Wifi was reliable. The manager seemed to be on top of it and checked with me occasionally to make sure I wasn't having problems.
Big double windows open to let a lot of air in. External blackout blind is nice if you like a very dark room when sleeping. The combo of the windows and the blind block street noise very well, no issues.
Bed was firm but comfortable.
Location was fine, but it depends on what you're doing. I did all the normal Paris tourist stuff with no big hassle. The Pere Lachaise cemetery (enormous) is walking distance from the hotel and SO worth it. Go there on a nice day, it's beautiful. If you like peaceful walks, trees, birds chirping, photography, or just getting away from the gong show and crowds of Paris, then give it a shot. Jim Morrison is buried there, among other notables.