I started with a K2661 then got a PC3 now I'm on a PC3K7 and I'll probably
always have a K board.
I'm not familiar with the PC161 but obviously there has been
some changes, but as you know Kurzweil are big on backward compatibility. It is rumoured
that there will be a new rom block arriving sometime (I wouldn't say soon) for the PCK
models and the PCK's also have the benefit of static sample ram.
For more info why
not head over to (can I do this?) Mastering Vast at http://www.cunka.com/forum/
It is full of Kurzweil players and
I'm sure someone there will know your current board.