I stayed in the Marriott a couple of months ago. It was perfectly fine. The room was a decent size, housekeeping did a nice job each day, and we found the location to be central to many places we wanted to go -- Recoleta and Puerto Madero are both within walking distance. However, as others have mentioned, it is an older hotel. There was a small pool area with a nearby restaurant/bar with hit or miss service. You will likely have a perfectly acceptable experience at this hotel, but it won't be incredible either.