Spoke to soon with the Nitris DX.
It was fine when I had it at the start which was 10.9.2.
Then came 10.9.3 which broke it somewhat.
Then installed 10.9.4 and felt it was fine with the odd errors here and there that would go away after a few tries of running app.
After a week of that, the app would not open due to the errors.
Back to basics and took another nMP brand spanking new with 10.9.
So far running Nitris DX again with Beta/XDCAM decks as well as AMA for MXF/RED files.
Ill keep it this way for a week and see if it breaks again.