I was in Berlin earlier last year and I was surprised at just how excellent the taxi's were, especially in comparison to the UK. As you say, all clean, high quality cars.
Ditto, was in Berlin recently and was very impressed by the taxi service. The taxi driver slowed down and asked us if we needed a ride, was patient when we got out our address on our phones for the AirBnB, and even suggested a faster route. He gave us a detailed explanation of the cultural sites in the area. €11.80 to take two people with 4 luggage bags about 5 kilometers.