We booked the hotel as my friend has stayed at other Rixos hotel/resorts, however this hotel was a bit underwhelming in comparison. It was wasn't terrible but not great either - average at best. Location is very convenient and walkable to the main shopping and dining areas and the Galata area. If you're looking for a quiet, relaxing hotel, this is probably not the hotel to stay in as the immediate area outside the hotel gets really busy with taxi traffic which can be heard in your room (which was especially annoying with the windows open).
The rooms are ok, kind of basic for a 5 star hotel as are the toiletries (I'd recommend bringing your own shampoo and conditioner) we had twin room and thought the beds were narrow but comfortable. There was no main light, so lighting was always a bit dim in the room. The bathrooms could really do with some ventilation as well. The mini chocolates at the end of each night were a nice touch however.
We didn't eat/drink at the hotel bar/restaurant - prices are very expensive and being next to Iskitlal street, you're not short of options as a plus. All on all, an Ok stay but am surprised this is considered a 5 star hotel.