What a lovely apartment, well worth a stay in Istanbul, and as described, the views are stunning. Istanbul is very hilly so you might appreciate using the funicular to nearby Taksim Square, which is also a hot-spot for nightlife.
One gripe would be the cost of the booked shuttlebus from the airport, infinately cheaper to make your own way, but being met at the door of the apartment block and being shown around was much appreciated.
Highly recomended.