We stayed for a month. I have never been to Acibadem before, but I am glad that we've picked this area of it and the flat is comfortable and spacious. We were able to cook there, and the balcony is really useful and big enough to have breakfast there. The flat is located in a very calm and green neighborhood. Close to the Nautilus (a nice shopping mall) and Metro/Marmaray (which will bring you to the European shore quickly). Also, you can take a walk to Moda to feel the buzz. We picked this flat as we are traveling with the dog, and there are enough green areas around to fulfill the needs, It worked out well. However, we got a medium-size breed which we can carry up and down the staircase, for larger ones it could be a problem, because of the steep staircase.
The communication with the hosts was exceptionally good. Both Umut and Osman Can were really helpful and responsive. We had a lot of bags and Osman Can helped us to carry them up and down and to book a taxi.
Next time I'll need to book a place in Istanbul it will be a no-brainer to choose this one. Ceck out Firuze Cafe nearby for some good desserts.