Sorry at moment the sampler of sd9 is not full ready. But soon you can have a new update with new funtions like realtime filter ecc. Only be wait a little time. As you know Ketron is not big like yamaha and korg, is a litte Italy company. So it's normal the time it's so long.
About the difference from sd9 sd7... there are many video youtube, and manual, but of course the big difference is not only the lanch pad but the live guitars, user audiodrum, the modeling is more big, the hardware is different, the touch screen , new sounds, styles, and much more