While this place is small, it's perfect for a couple of days in Paris, and the bed was surprisingly comfortable.
My one recommendation is on baggage. Laurent points out that you have to carry your bags up some stairs, so you don't want them to be too heavy. I would also recommend that your bags not be too large. I was using a 24" bag and it was a bit of a struggle to get it upstairs without making quite a bit of noise when I arrived late at night, as the staircase is narrow and curving.