The same orchastra BPO. Kissin was about 19 and his 1st appearance with Karajan, looked a little tight. Lang Lang is about 23. Both have great techniques, prob the best among their generation.
The 'PK' in the title nonwithstanding, by playing them side-by-side, one can learn a lot about how the best pros approach their music making. We find our own taste(s) in the process.