I suggest Down to the Wire and The Marmalade King on Hat. Not recent stuff, but good examples of his work. After all, he is an old dog.
As for this box, it sounds like the format is much the same as the Clean Feed box with Joe Morris. Four duets, each about an hour long. Completely improvised. The difference is in the relationships. Morris didn't have much history, if any, of playing with Braxton whereas Hemingway did.
The Joe Morris was a pleasant surprise to me. I thought they work quite well.