When I start to listen a band I never listened before, I NEVER start with a live album. Although it covers (probably best) songs from different albums of that band, usually, it can never be as well-produced as a studio album. (so I'll buy a best-of instead)
And for an artist like Bruce Dickinson, production is essential. By production I mean layering of guitars, layering of vocals & back vocals, guitar tones, effects on instruments, song transitions, fade out's, synchronisation, extra fills...
Best-of albums lacks the consistency of a single studio albums. songs from different recording sessions, different approaches, sometimes different musicians... it lacks a total cohesion.
What's the next Bruce Dickinson to buy after you got introduced? after a best-of? Two options are Accident of birth and Chemical Wedding.
If you prefer to sit back, have your headphones and listen carefully every song, caring for production and musicality, I'd recommend CW, because it is
1) a concept album,
2) all the songs are equally great
3) production, guitar tones are superb and add a lot to the music
4) it has some best guitar solos I have ever heard (King In Crimson...) and some best fitting guitar solos to the feel of the song (Chemical Wedding, Jerusalem, The Alchemist...)
But, I can also recommend Accident Of Birth, it has:
1) songs in many different styles (from heavy-as-bulldozer Starchildren, to mellow peaceful acoustic Arc Of Space, from epic-like Darkside Of Aquairius to 80's rocker The Magician)
2) again, some best guitar solos I have ever heard (emotional Taking The Queen, extensive dual guitar solo Omega)
3) again production shines on songs like Taking The Queen, Man Of Sorrows, Omega
4) it is more riff-based, so it's catchier, yet still rocking as hell.
all in all, AoB songs are less coherent, yet still consistent. they are more independent. and for me, some of them are better than any CW song.
So the choice is yours according to these conditions [!--emo&

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