The most authentic Diner in France is probably this one, I love the way they designed the restaurant front. It really feel like it is a copy from a downtown Diner of Manhattan.
Inside, you will find good atmosphere. Both the decoration and the staff are nice. The daily menu or Brunch set menu are nothing special: eggs, pancakes, hamburgers, wraps, milkshakes. Typical.
However my good impression about that place stopped there, just after I saw what products they use. The food quality is below the average in Paris, really cheap. I think that nothing is really home made. Do not expect fresh food, but industrially processed stuff. Avoid the vegetarian steak which is tasteless…
The restaurant is crowded most of the time, it is popular because of the affordable prices, but also due the opening hours. So, expect to line up, especially for the brunch which worth the 16.5 euros per person.
To conclude: It is a good place to spend time with friends. They have some large tables. Problem: each table is so close to the other.