Its an old building in an old neighborhood, and like any old building it does come with its set of issues here and there, but the host responds right away to any concerns you might have and there is a concierge right next door available 24x7, who can also call a cab for you at anytime if needed.
The rooftop is not as big as the pictures make it look but still lovely and provides one of the best views of the city and Galata Tower too. There area is centric, close to the train station, safe and there is everything you need within a couple blocks or less.
I will definitely stay here again next time I'm in Istanbul, just the location alone is by far the best value!