I am ever on the hunt for the perfect croissant. When I read that this pastry shop (which happened to be close to where I was staying) possibly had the best in all of Paris, I had to investigate. It was a cute cafe with a line out the door - which isn't saying much since it's a tiny cafe. The croissants were excellent, though they don't stand out in my mind as the all-time best. I didn't get them fresh out of the oven though. The coffee isn't the best, maybe get your pastry to go and enjoy them with a superior cup of coffee elsewhere.
Overall, the neighborhood is pleasant and the cafe is worth visiting if you're in the area.