We had a very nice experience staying at Lederegasse.
The apartment was extremely well cleaned when we arrived, it has personality and is situated perfectly near Vienna center, the Museums quarter and everything you need.
Right on the other side of the apartment you find the more young, hip neighborhood Neubau which is also a great experience.
As a fun treat we learned that the artist Gustav Klimt had his studio nearby on Josefstädterstrasse, which we passed everyday.
I highly recommend staying there, should you want to experience the best of Vienna.