Dominik is nice and friendly but you probably won't meet him a lot. So if you place importance on getting in touch with your host Dominik's offer will probably not be the right thing.
His place is something between a hostel and a living community. He has several rooms for rent, so you have to get lucky when it comes to your temporary flat mates. But there are features that do not go without saying for the usual Airbnb offer: you have your own set of keys, including one for your room, there are two bathrooms and two separate showers and you can leave your luggage after check-out and get it later, which is quite nice if your flight goes in the evening.
What else is there to say? The flat is clean, the rooms are small but sufficient (in my case with a wardrobe, a mirror and a fan), the bed is ok. There are two U-Bahn stations near the flat and the Westbahnhof is in walking distance (or one U6 station ahead) where you can find the so called U3 Supermarket which is open daily until midnight (Sundays as well).