Nothing fancy as I am just learning Hauptwerk, and (I must admit) re-learning how to play the organ.
Years ago I played the trio's by Sorge as part of my organ lessons. My fingers and feet partly remember how to play them, so they are a appropriate starting point.
The sample set I use in this recording is a free one from virtual-organs.nl, playable in the free version of Hauptwerk.
No money yet for the grand sample sets. Perhaps later.