Yamaha has some fantastic lead sounds. I found great guitars, new Pianos and Trumpets were good. Drums not as good to my ears as PA4X. I like organs on the 4x better, especially the way the lelie sim works. I'd say it is really close. I like the sound of both.
As far as the groove, not sure exactly what you mean, but I'm assuming it's a "live" sound. The variations in the Revo drums does add some feel to the styles. It's not anything I was missing on the Korg, but way better than PSR. For example each time a snare is hit, there is a SLIGHTLY different feel because the Genos varies the place it was hit on the snare. Pretty neat!
I couldn't really tell much difference in the styles from the PSR, but I didn't have them side by side. I do have several of the Genos style on the PSR and I didn't notice much, if any, difference in the way they sound.
Bear in mind this was still a fairly limited session and I didn't explore everything.
Only e.q. I did was to boost the last two bands on the high end from the FLAT preset. I tried all the Presets and that sounded best to me, through Don's two Bose Compacts.
It seems to me they are leaving a lot of things to adjust by the user, but I suppose that's not all bad because it's easy to do.
I would have to change at least the volume on almost every OTS button.
I do like that the programmable sliders are labeled and it is quite easy to adjust volumes and style part volumes on the fly. In almost every style, I had to raise the RH volume to 127 (full) for it to be heard properly. Default on everything was 100, but if I left the RH level there it was too soft.
Bear in mind that these are all minor things and can be readily and easily changed and saved to Registration, or even to User Styles.