I really wanted to try out Maison F next time I was going to be in Paris. We got quite late in the afternoon but the staff was kind enough to let us eat (if we picked quickly). If I am going to be honest the food was a little disappointing but was good lunch food nonetheless. We might have just chosen in haste and thus chose badly.
However, we weren't there for the 'food' we were there for the fries. Maison F is the only fries bar in Paris and the fries are actually really good. I would highly suggest you stop by here if you are looking for somewhere to grab a bite before you go out for the evening or in between museums and shopping sprees in Paris.
3 Rue Rougemont
75009 Paris, France