Most if not all the albums are available on CD. There are vast numbers of compilations (beware of bootlegs), BBC concerts with orchestra and rarities.
But the early works are the best. The first album, despite its weak points, is an enjoyable listen and deserves more attention than it gets. It was genuinely experimental.
The third album, And Other Short Stories, is a highlight. Recently it was revisited and ‘finished’ in the way that was originally intended. There’s not a bad moment on this.
Of the later albums, Octoberon is one we use for turntable testing, Ring Of Changes is much disliked by fans but we enjoy the very different sound.
Solo albums by three of the band are of some interest to fans only.