Excellent plugin. I was using Pianoteq with a KX88 and it was a superb combination. But my KX just died after 35 years so now I'm snooping.If software is on the table, Pianoteq is quite good. Not only does it sound great, but they’ve done an amazing job with emulating the responsiveness of the software to feel like a piano, even with a MIDI controller.
For hardware, I’d echo the comments of others that Nord and Dexibel are among the best I’ve heard.
The two best Piano Sounds (IMO of course) are found in Kontakt 6 and Logic EXS24 when loaded with either the Garritan Abbey Road CFX Concert Grand sample set or Spectrasonics Keyscape Collector Keyboards (the LA Custom C7 Grand Piano). And I would recommend the Synthogy Ivory II Grand Pianos (based on a Bösendorfer 290 Imperial Grand, Steinway D Concert Grand, and Yamaha C7 Grand) but it has some 'challenges' for me. The issue I have with it is the size of a the fully loaded sample set - 77 gb!, the USB iLok requirement and even though it's gorgeous sounding it's modeling technology versus a true sample set.I like the Nord piano tones and Kurzweil has some good ones. Who else has good realistic patches in like a 73 key semi or weighted keys?