It is hard to overstate what a great location this apartment is for being a tourist. Very near the center of the tourist sections in Berlin, and near the Surface rail which goes everywhere.
My wife and I were there a week, and found it quite comfortable with everything you would want to stay a day or a month. The train is very close—we bought a week pass and went all over Berlin easily.
Grocery store a block away so we cooked about half our meals, dishwasher and clothes washer in the flat. The space is about perfect size for two people. And the windows and doors are nicely soundproof.
(And the Vietnamese restaurant across the street was excellent!!)
I will definitely look to stay there again.