I was hesitating which piano I should buy. Yamaha and Kawai as well have very sharp sound at higher notes. Not this Korg. I most often use headphones .
* I tried some old AKG headphones but those I like best are T Bone HD 1800, or Superlux HD662F. These provide nice sound in entire range.
*It sensitively responses the dynamics.
* Its speaker doesn't make the best sound, especially bases sound like in the cave, huge soundfull. Not like real strings. Lower sounds really annoy me.
* It has also some strings samples and other piano ones, including honky tonky and harpsychord.
* You can switch the briancy - that's cool and useful.
* I use it for recording basses to my band stuff, does great job. Either piano sample or Bass guitar which is exceptional!
120 polyfony is enough even if you play some Liszt stuff. Don't know Rachmaninov , that's not my league.
So at the end of the day I can say, I am really happy with this instrument still after 4 YEARS! It's much better than more expensive ones !!!! Definitely I am recommending this one.