They story of Quicksilver Messenger Service, one of Haight-Ashbury's original psychedelic bands, is a muddled one to say the absolute least. At first Q.M.S. were to be the vehicle for proto-hippie troubadour and guru-like character Dino Valenti. But getting busted for marijuana in 1966 resulted in hard time. With their leader temporarily out of the picture, Quicksilver ditched folk-rock for LSD-inspired jamming that showcased guitarists John Cipollina and Gary Duncan. The duo exerted a considerable influence not only on the Allman Brothers' Duane and Dickey Betts, but also on any '70s hard-rock band boasting two ferocious leads. To hear a band every bit as groovy and "out there" as early Dead and Jefferson Airplane, simply crank Quicksilver's masterpiece Happy Trails, a sprawling and often orgiastic rebirth of the Bo Diddley groove. In 1970 Valenti returned to the fold, forcing the group to revert back to its original -- if inferior --sound. This led to a fracture after just two albums. Since the mid-'70s Quicksilver have gone through too many personnel changes, breakups and reunions to count. Usually, the only original member is the great and underappreciated Gary Duncan.