I stayed in this apartment for 4 days and it was everything we needed. We were a big family with childern (11 people in total) but the apartment was very specious and more than enough, especially the 4 showers saved us a lot of time before we go out in the morning and before we go to sleep at night.
The location was excellent, it was in a local neighborhood so no hotels or tourists around. However, it was really close to tourists attractions, 2 minutes walking to Galata tower and 2 minutes walking to the start of Istiklal street (which is a plus because you can from the apartment to Taksim square and not miss anything).
One more advantage, no steepy street. My elderly parents can walk everywhere without a problem.
Overall, excellent :)