We spent 5 nights in room #2 on the 2nd floor of the Hotel St. Jacques in late June/early July and had a pleasant stay. Room was of a decent size, had a very quaint decor and, more importantly, had an excellent working air conditioner which my always-too-warm husband appreciated. A/C was quiet, had a digital thermostat with high and low fan setting and individually controlled per room.
Hotel staff were friendly and helpful, all seemed to speak English well enough. They helped us to book a shuttle to take us to the airport.
Location was great. Close to metro station and lots of restaurants. Within walking distance to the Notre Dame, Pantheon and Luxembourg gardens. Groceries, ATM, and everything you need nearby.
The walls aren't very thick and we heard people in the adjoining rooms once (as they were loud) and a fair amount of noise in the morning (we're not early risers) from inside and outside the hotel but it wasn't a big problem for us.
We did have to pick up and drop of keys at the check-in desk in the lobby every time we came back and left the hotel. They always keep the keys to the room and this also wasn't a problem for us.
Our photos of this hotel are posted at http://travel.webshots.com/album/573356922nkPuFU