If you're into Live/Evil then I can't stress enough how much you need to get your hands on
The Cellar Door Sessions 1970. Trust me, it's worth it. Six CDs and a lovely 100 page or so booklet, containing the full recordings of the band’s Cellar Door residency, from which all of the "Live" side of Live/Evil was taken. Arguably one of the very best Miles sets. I’ve listened to the various takes of “What I say” on that just a crazy number of times.