Myself & 5 pals stayed here in April this year (2015). Brilliant location, all amenities you could need very handy. Apartment clean, spacious and had outside space too.
The entry & leaving of apartment very easy too. Would definitely recommend to anyone visiting Berlin.
Train stop just round the corner, but we even walked into City Centre one day. Great city to visit, very cool, quirky and full of history. German people very friendly!! We had a great time and will be back!!