I liked the two-parter. The second part was a little less exciting but that's not unusual.
There was a lot of classic who-feeling and it was nice to see some doctor who without the pseudo-profound self-centered character reflections that seems to dominate every second episode.
edit: Oh, I forgot: I didn't like the Beethoven thing at all. if this show goes on for another 50 years, will there be artists left that did their work without the doctor's help? And Beethoven wrote more than symphonies and concertos.
Still, comparing to the other episodes it deservers 6 stars. (edit 2: oh, only 5 ... then 5...

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