One of several outstanding live small-group records Braxton recorded in the mid-to-late 1970s (with Dortmund 1976 the (not unjustly) most heralded), Performance was issued initially on LP as Performance 9/1/1979, and was first issued on CD as Performance (Quartet) 1979.
It has been unavailable for years, and has recently been reissued by HatHut/HatOlogy. http://www.hathut.com/covers/610b.gif
Good news, good news.
I'll give my copy a listen soon and try to collect my thoughts about this recording.