Getting there from CDG: Take the RER B and then walk 10-15 minutes. We got there at night and the area was popping with people eating and socializing.
Getting to the room: Entrance is easy but be warned about the staircase. We were on the third floor and had to climb with the suitcases. That is fine, but the stairs themselves are half the width of a normal step, so there were many times I almost fell. My friend hated these stairs.
The room itself: Very tiny but liveable. There's 2 tables to get ready or eat on, a tv, and the most compact bathroom/kitchen ever. You can't move in the shower because it is so small. All other amenities were fine, and I would've loved to use the washer if I had stayed longer.
I would recommend this to young people or solo travelers because of it's proximity to Le Marais and the museums/Seine. You can also hear people in other apartments or if someone in the courtyard, but c'est la vie.