We stayed at Apostrophe Hotel from 29th to 31st January 2012 and throughly enjoyed our stay.
Everything in this hotel seems to be done with love and care. The rooms are beautifully decorated around different themes, everything is very clean and the staff at the hotel are lovely - nothing was too much trouble. They provided tips about where to eat, how to get to the sights we wanted to see and even made a dinner reservation for us. We had breakfast in the hotel both mornings and enjoyed it very much. This included freshly squeezed fruit juice that the staff had made that morning. It's the little touches that make the difference.
We stayed in the Paris Paradise room which is on the top floor of the hotel with a view out over the rooftops of Paris and the Eiffel Tower in the distance. It really is stunning to see it all lit up at night. The bed in the room faces the window so you can wake up to a view of the Eiffel Tower. As has been mentioned in other reviews, there is a jacuzzi bath in the room itself so if this doesn't appeal then choose another room (other rooms in the hotel have three way directional showers).
The hotel is well situated, around ten-fifteen minutes walk from St Germain which is a nice area to stroll around. There are lots of little independent boutiques and cafes in the area and it is close to Palais de Luxembourg. We found it to be very quiet in the hotel at night and didn't hear any traffic noise at all.
We had an absolutely fantastic time when we stayed here - in fact, we're planning when we can go back!!

The hotel looked amazing, the room was stunning, clean and comfortable. We couldnt have asked for a better place to stay. The staff could not have been more friendly or helpful. There are 3 stations close by which will take you directly to anywhere you want to go in paris. Excellent hotel. I cannot recommend it enough.

Stayed at the Apostrophe Hotel for one night as part of a birthday - weekend trip.
We had one of the larger rooms with the jacuzzi bathtub.
The hotel is very clean and quiet (no street noise at night) and nicely decorated. Complementary toiletries included shampoo, conditioner, bath salts, body lotion and hand lotion (quite extensive selection compared to what you often get in other hotels). The rooms aren't so small for what is normal in France - and there is plenty of space to store your suitcase etc.
The receptionists were all friendly, and the hotel is less than a 5 min walk from the Vavin metro stop!

Nice small hotel very friendly staff... rooms are not very large (a little small though)
Location for those that knows a little Paris is just very good for shopping (not the best if you are ONLY looking for Luxury shops... located in the heart of Montparnasse you are close to St Germain, Restaurants, movie theatre, find Taxis and all kind of transport very easily.
I just think it is a little overpriced for what you can find in the area...