Coffee Shack is paradise. Great food, awesome location, nice day trips. The shared bathrooms were clean, spacious and nicely decorated. I stayed in the Rond dorm, which was spacious enough. It's close to the bar so it can get a bit noisy. The Hall in the Wall Hike was great. The area around Coffee Bay feels a bit like The Shire from Lord of the Rings, just at the ocean.
Loved the place! Great food, awesome views, spacious dorm (Blue dorm) with two different rooms + veranda. Cintsa is a quiet place, great if you want to get away for a view days. But you can also have a great time at the bar at Bucks.
The staff was nice and helpful, the room was clean, the design of the Hotel is colorful and modern. The breakfast was free for us and the selection was ok. There's a bus going to the Opera and the Eiffel Tower almost in front of the Hostel (line 42), which was very convenient. Additionally, the metro and Garde du Nord are really close. Although the area around the Gare du Norde didn't seem so secure and nice like other parts of Paris.