Hi madsynthman,
I have a "Y2K" (PSR2000) I`d say get the "Y1K" (1000)
The Casio is indeed a good KB. My first "arranger KB" was a "Casio" and I enjoyed it for a number of years. A-side from some voices and "vocal" the 1000 is just about the same (only 32 poly). Have you checked 2000 prices? I think for the extra $$ you might enjoy the "Y2K"
O-BTW, Welcome to our family and the best corner of the web
You could not have found a better place !
Great "bunch" of people and we are here for each other, so let us know how you made out !! Good luck
jedi