Thanks for your comments. As you know, Pianobook is not just a resource, it is a community. As such, you can help us by picking an instrument you particularly like in Kontakt, and translate it into a free format such as DecentSampler or SFZ. Then upload it back to the community.
If everyone did just one translation, we would quickly have free open versions of all the instruments (we need about 300 done).
Can you help out?