I did the upgrade first which went well, only the audio needed sorting. I found though that some apps that I use regularly were misbehaving so I then did a clean Unibeast install. Bad mistake, lot's of issues with Adobe Photoshop, MacCleanse, LittleSnitch to name but a few. Untennable! So it's back to restoring my El-Capitan backup and then applying the upgrade again. Then waiting patiently for the app authors to sort out their twisted kni***rs.