A six-CD set of everything Fleetwood Mac recorded for the British Blue Horizon label. Wait, you're saying, didn't they only do two albums for Blue Horizon before leaving the company in early 1969? True, but there were also the non-LP singles that comprised the bulk of the U.K. compilation The Pious Bird of Good Omen, the two albums of blues jams in Chicago that came out later in 1969, and the 1971 LP The Original Fleetwood Mac, comprised of early outtakes. Make each of those half-dozen LPs a CD, add some outtakes and alternate takes to each, and you've got a pretty full box. Unintentionally, this box makes the Mac a candidate for Most Erratic Major Rock Group of the Late 1960s, ranging from the sheer brilliance of Peter Green's songs to rote blues covers that are downright mundane, particularly some of the Jeremy Spencer showcases and Chicago blues jams. If you're a committed enough fan to consider buying this box, you already know that; you're probably more concerned with whether the previously unreleased material merits the cost. Those extras are marginal, to be honest, comprised largely of false starts, incidental studio chatter, and alternate versions that are pretty close to the official takes. Certainly the highlight of those newly unearthed tracks is the 37 minutes of alternate takes of "Need Your Love So Bad." It's also nice that the Danny Kirwan tracks that appeared only on the U.S. album English Rose are here as well. Unfortunately, this is not a complete retrospective of the Peter Green era, whose best material was recorded for Reprise; there's also a lot of noteworthy live stuff that appeared on different labels. Looking for more reasons to get the box anyway? There are extensive notes by producer Mike Vernon, which incorporate a few comments from Green.