Hello Don and Donny,
With my X1 I use the factory/custom feature to alter the voices of the styles . No registration's . Every voice of a style in each variation can be altered and saved. I also enjoy the fact that I do not have to page through menus to access the volumne controls of the parts .
Most recently I have been interchanging styles to create new mixes .
Real time mixing is I think much easier on the X1 vs PSR9000 .
That's why I have always enjoyed Ketron.
Wait til you here the SD1 . Maybe we can convert you both back to Ketron ? Dan o