UPDATE 2023
The IRCAM Prepared Piano 2 is an IRCAM production in collaboration with UVI. This is a VST that simulates both the piano and the prepared piano, based on more than 12,000 high quality samples for a library of approximately 18 Gb. In addition to various types of piano, 45 types of preparation, extended techniques and effects are emulated, all well described at the link above. Price $ 209.