This is a spacious apartment (for Paris!) very conveniently located between Place de la République and the Châtelet-Les Halles transit transfer point and shopping center. It's also walking distance to Le Marais. I didn't have to walk more than 5 minutes to find food or a Métro station.
It's quiet at night since it's a bit higher up. Attention, though, as it is on the top floor so there are quite a few steps to climb up.