I guess the album most comparable to this in rock history is probably Bob Dylan & The Bands The Basement Tapes. Both were released in the same year and featured tons of unreleased material from around the same time. That's where the comparisons end though. They're polar opposites musically as Dylan was subtly creating proto-Americana and casting an illuminating view into his reclusive years, with the best backing group in Rock at his helm. As such, that album has become a cult favourite and one of his best releases of the Seventies. Metamorphosis, however, is an unfocused odds and sods set of sixteen tunes with next to no cohesion holding them together. Thankfully, second-rate rejects from the Stones still happen to be stronger material than a lot of bands could ever hope to have composed and, as such, these songs are still worth a good listen.