Sorry to be slow to reply.
Editing was in Final Cut Pro
It's true that not everyone in the band loved the edit with all the boxes over the second edit which was a little more traditional, but I managed to argue that we go that route as it hid all the different color balances. Also it hides a bit that there is no camera movement in most of the cameras.
Not sure how the sound mix was done. They captured the monitor mix so grabbed all the instruments individually and then remixed it adding a little atmosphere from the audio from my main cam
Yes, shoestringconcerts is right, the GoPro's do need a lot of light. It's a good point.
All in all a lot of fun considering I had 24hr notice to get ready so really was just flying by the seat of my pants for the shoot.