I spent 2 nights at the Azade Hotel on an RS Turkey tour 2 years ago. Before the tour I stayed for 6 nights at the Erboy Hotel.
It's not clear if you are looking for a hotel recommendation or considering whether to take the tour, based on the hotel.
The Erboy had modern decor. The Azade had traditional Turkish furniture and feel. Both beds were comfy.
Both were good locations. The Erboy was close to the trams and supermarket, easy walking distrance to some sights (Galata Bridge, Spice Market. The Azade wasn't, but it was very close to some of the top sights, Blue Mosque, Hagia Sofia.
The Erboy had modern elevators from lobby to all floors. At the Azade there's a winding flight of stairs down to the lobby, then either stairs or an ancient, small, slow elevator to the rooms and terrace. The breakfast at the ERboy was much better, but the Azade's was fine. The Erboy staff were well informed and very helpful. The Azade's were neither. When I arrived they assigned me a room in the annexe, which meant going up to the courtyard, then up a flight or two to the room. When I refused, they found me a nice room in the main building that had a (somewhat obstructed) view. The Erboy rooms didn't have views.
The Erboy's internet prices were a lot lower than the Azade's.