This is the preferred approach for me. There is no magic associated with 5 or 6 or pick your number. Just add in more of the bands that you love. I could never leave out Genesis from such a list, and look forward to seeing the Musical Box on Friday in Denver at the Paramount Theater. For non progressive music, Hot Tuna is playing the same venue on Thursday night.Why not just make it the 6 most important prog rock bands and add Camel?