I have a boxed, new and unused ASIB1 which is surplus to requirements (after a long search I found an EX5R with one already installed, thank you tux!).
If you have a working digital output (EXDG01) that you're not using, but would like some SCSI action, please get in touch.
Most would agree that the EXDG01 is more valuable than the ASIB1, and I'd be willing to pay a (reasonable) difference.
The EX5 features a unique Extended Synthesis system which incorporates a number of advanced tone generator technologies. AWM2, AN, FDSP and VL. The EX5 is one of the best keyboard Yamaha ever produced.