Well you've reached a Kurzweil employee. The K2500 Zone is run my me, Mike Martin of Kurzweil. Depending on when you called Kurzweil, its likely that most everyone was at the NAMM show. You are also probably not a service center so were not usually good about giving end users this kind of information because of the liability involved.(posted 9220 days ago)Regardless, yes the ROM boards are the same, the daugherboard is different. If you have any other questions feel free to email me directly.
Have a nice day.
Mike Martin - Kurzweil Music Systems Kurzrep@aol.com