Don M good luck with your new KORG Pa4x,...I Know you'll do great things with it. As for Myself I've learned my lesson the last few changes... and will wait for the next Yamaha TOTL offering as I am not in a rush to change at this time. And with some of the the S970 styles sounding great on my S950 there was no need to change.
I do like what I hear in the BK9 especially the block chord organ but it's just not my cup of tea.