It's easy to forget that Hendrix only released three studio albums during his lifetime (not counting a few compilations). This live record is one of the only other albums that saw release before his death, and it was only because of a contractual obligation that it was released at all.
After dropping the Experience, Hendrix teamed up with Buddy Miles and Billy Cox to form the Band of Gypsys, and the trio recorded a series of live shows at the literal very-end of the 60's, on New Year's Eve (and New Year's Day) 1969/1970. The six tracks here are from those shows.
While the recording on this record isn't fantastic, the songs are. Hendrix all of a sudden seems a lot more bluesy, a lot more black, and a lot looser. That can be a good thing or a bad thing, I suppose. The first side is comprised of only two songs, the ten-minute "Who Knows" and the almost 13-minute "Machine Gun." Both are brilliant, and though they do seem long, the jams are oddly hypnotic and rarely wanky.
The second side isn't quite as strong, with two solid Hendrix compositions sandwiched between a couple of Buddy Miles-penned tunes that don't seem to carry the same weight. Of course, Hendrix steps it up, but it's his solo on his own "Message of Love" that is the highlight of the whole side.
As a historical document, this record is incredible. As a full-on jam, it's great as well. If you're looking for the controlled tenacity of some of Hendrix's more succinct songwriting, it ain't here. But I've listened to this album hundreds of times, and I always find plenty to like on it. Especially on those first two incredible songs.