I've played the PA900 for a few hours now. Sounds good, easy to navigate, since I already know the OS. In fact there are some improvements in the navigation.
I am disappointed that a number of my favorite styles from the PA3x are missing, including Blues Shuffle, which has been on every Korg from many generations. Also Big Band Shuffle, which I cannibalized to make a country shuffle. No real problem since I can find them and load them into User or Factory slots. Every category has a smaller number of styles. Just a little extra work if I decide to keep it.
I'm sure the sounds from the PA3x are better, but I can't hear it.
Vocal Harmonizer works great. It is not as complex as the PA3X, but does everything I need it to do, and access to make and save changes is easier. Headroom also is better on the input.
1/4-inch mic input is a step backward.
No wall wart, but a dedicated power cable. I think it looks like the same one that Tyros used to have, but not sure.
I would have to get a midi foot controller of some kind to address at least three functions. The 900 comes with Volume, Sustain and one Programmable. It does not accept EC5. Wish it did.
I think I actually like the organ drawbars on the touch screen better than the real ones on the 3x. Ones on the BK9 are still better.
I do enjoy the BIG touch screen.
Wish I could take the features I like from the BK9 and combine them with this. That would be a killer. Almost makes me want to keep them both! Almost.
Time to sleep now.