I guess I would say that my system was built for that purpose as well since prog rock, new and old makes up a significant portion of my collection. But ultimately, I found that the things that make the great prog rock great, are the same things that make orchestral and certain big band works enjoyable, at least to me - the ebb and flow, the large scale dynamics, and the intricacy. So I selected components capable of both detail and bombast, and landed with Jeff Rowland and Aesthetix for amplification, Simaudio and VPI for sources, and Wilson Audio for speakers. And yes, I always bring the first Gentle Giant album along to audition equipment.
Cheers,
Cheers,