By licensing these previously unreleased live and studio tracks (plus some previously released but rare material) from the Special Markets division of EMI-Capitol Music, the mail-order company Collectors' Choice Music has legitimized Quicksilver Messenger Service recordings that had floated around on bootlegs and quasi-legal discs for many years. The performances all date from 1967-1968, a period during which Quicksilver consisted of lead guitarist John Cipollina, rhythm guitarist and singer Gary Duncan, bassist David Freiberg, and drummer Greg Elmore. As Richie Unterberger points out in his liner notes, "They were not so much singer-songwriters as they were virtuoso players and creative interpreters and stylists. They were not the greatest of vocalists or composers"…