Just based upon the clips
Disc one sounds like general McCarthy. The Die is Cast could be Way of the Warrior almost note for note. Though the Far Beyond the Stars clip sounds pretty good.
Disco two I must say I compared the clip of A Call to Arms to the actual scene it airs in and my god they really mixed down the music in the final edit. I would wager they reached a compromise with the composers during the DS9 and Voyager era, we'll allow more interesting music through (as compared to late TNG) but we'll just mix it down so it won't make a difference anyway.
Disc three looks the most interesting but the clips offered are so-so. Looks like Richard Bellis get's 1:55 of disc space? What's the point!?
Disc 4 looks decent as well. The spy music sounds like fun and the fight music for Trials and Tribble-ations seems as if it suffered the same mixing down problems in the final episode. Is it me or did it seem there was a brief ode to some TOS style fight percussion at one point? I could be just imagining that.
Definately looks to be a far more interesting listen compared to the TNG set.