I agree entirely on his Beethoven interpretations. They are for me, definitive. Karajan introduced me to Bruckner, as well, and for me, Karajan’s Bruckner is also definitive.
(Not to imply that I am more knowledgeable than I am...I’m just saying, “I like what I hear” and everytime I say that, it seems like Karajan is at the podium...)
Especially the 6th.