You will not find a better location. It is literally 50 metres from the Hauptbahnhof.
Apartment was modern and very clean. This is an apartment-hotel which means regular cleaning service. Check-in is automated and efficient. I was in the apartment for a full month. I had only one issue during that month (I left my key locked in the apartment). Hotel management quickly solved the problem. I had absolutely no complaints about my stay and recommend Apartment-Hotel Batu highly.