OK, so this is a pretty unnecessary compilation album of Queen's heavier side, though it's impossible to argue with the quality of the material on offer.
What makes this really worthwhile for the non-casual fan however are the two new tracks - 'No-One But You' doesn't really fit in with the theme of the album, being more of a ballad, but it's nice to hear Brian and Roger sharing vocals on this tribute to Freddie. There's also a 'retake' of 'I Can't Live With You', which basically seems to involve Brian, Roger and John going back and re-recording some of the guitar, drum and bass parts of the song while (obviously) retaining Freddie's vocals. It's not THAT different from the version on 'Innuendo', but it's still worthwhile hearing a new take.
By it's very nature, this will appeal either to those casual fans who haven't yet decided to take the plunge and buy the bands complete back catalogue, and the hardcore faithful after the 2 new songs.