I really loved staying in this apartment!
It wasn't my first time is Paris , so I firmly state it is quite big for typical Parisian studio, it's spacious and full of day light. I never saw or heard neighbors, nor any sound from the street -- super quiet place.
It is equipped with all necessities such as washing machine, very cute tea pot and nice set of dishes. Whole apartment is decorated tastefully and not overstuffed. I wish my own apartment would look like this one.
As for location, you couldn't find better one. It's super close to big interchange station Les Halles where you can take train to basically everywhere. Louvre is 5 minute walking distance. Across the street there is bio super market and small shop where you can get food and drink even at night.
This place is a perfect choice for long or short term stay,