Mark & Mary Ann Weiss have been working with the Post Organ Toolkit and have been getting amazing results with it. They created a sampler based huge organ system with 10kW sound system with fourteen 18\" subwoofers to ensure graceful reproduction down into the infrasonic region.
They present two audio clips on their website that are so realastic I want to share them;
Bach: Fantasia & Fugue in G minor BWV542 using mainly HAUPTWERK, Flute and Roerflute.
The other piece Dupré: Carillon Op 27 Nr. 4 is even more like the real thing; a relgious experience!

Michiel Post