We stayed for 5 nights in late November. It was easy to either walk or catch a tram to Hacketscher Markt and MuseumIsland. We stayed in the Parkview Suite Azure. It was a studio apartment but well designed (with a separate bathroom.)a balcony overlooking the Park and very quiet. There are great supermarkets within 10 mins walk. On the ground floor there was a good if basic Italian restaurant (which does breakfasts if required). The highlight was the restaurant in the park below - "Nolas". Best restaurant we dined at in Berlin. Swiss cuisine with excellent fondues and salads. Its very popular so you need to book.
The owners live in the apartment complex and are very efficient - Stefan lent me a tie to attend a wedding !
First time visit to Berlin so we did a lot of walking. We liked the Mitte area in former East Berlin. Quieter and more ambience than some of the more modern parts. If we visit Berlin again on our own, we would definitely re-book