Yep, Yamaha re-purposed the VKB-100 Vocaloid keytar. The VKB-100 has 13 musical instrument patches in addition to the Vocaloid sounds. Yamaha reused the same hardware platform for the SHS-500 Sonogenic. They tossed away the Vocaloid stuff and add more instruments.
Ignoring the play-along aspect, it's like a polyphonic Reface ROMpler with the waveforms and effects taken from entry-level PSRs. Street price is $300 USD.
More thoughts, rambling and a list of instruments/drum kits at:
