I had a great stay at this hotel. The location is perfect, in the lively neighborhood of Galata. You can go to the shared terrace whenever you want (before 1am): the view is amazing to breakfast there or a drink in the evening.
The staff was nice and helpful, they speak Turkish, English, and Russian. And overall it was an incredibly good value for money.
I definitely recommend it to anyone for a short stay of a few nights.
The only issue was wifi: internet was often slow, the best I had was 8Mbps download according to SpeedTest. But I didn't tell them and they were doing some work at the same time in the building so that was maybe the cause of the problem.
Also make sure they give you the same room as the one on the photo when you arrive.