The apartment was very nice and was as advertised. The owner was very good to deal with and very responsive.
I would call it hotel room sized, but it served our purposes well. The apartment is not especially conducive to cooking as it has only a hotplate - if you are accustomed to using one maybe that would be acceptable for you. We did not arrive expecting to do any cooking in the apartment so it was fine - and there were plenty of places to eat in the neighborhood.
The location is great, very close to the museum quarter train stop and in the heart of a very popular shopping area. The downside then is the crowds and the noise, but that's the tradeoff for the great location.
The actual getting into the apartment made me feel a bit like I was running a clandestine spy operation, but it was fine and the owner laid out the steps very clearly and we had no issues.
I would absolutely recommend this location for a couple, no more than that, who want to be in a convenient (if somewhat noisy due to the proximity to the shopping district), clean apartment.
Hope this is helpful.