Many times there are variations between all those versions. We have singers who know what version they want and if it isn't available they won't sing it. Some are even picky enough to want a particular brand. My sister-in-law was doing a show in a new location and had a couple who specifically wanted Sound Choice (some of the worst quality CDs
) versions only for everything they sing...go figure. But anyway yes I would keep all of the versions....just in case.