If you get footage graded in Red Cine X and bring it into DaVinci, it will often look somewhat different.
In Premiere, it looks identical - so this is not a Red SDK limitation, it is purely a DaVinci issue.
It doesn't always fail - it seems that the grading done on the Lift-Gamma-Gain pots or curves of RedCine X (if any was done) translates with imprecision, whereas the rest comes through fine. If no changes were made to the pots or curves then everything looks the same, and as it should.
This is a huge inconvenience.
Before anybody offers this suggestion "apply metadata curves" I have tried off and on, and yes, my monitor is calibrated and the video card output matches the BM card exactly. I also am fully familiar with how Red Files are only updated once per project (although this too is annoying - there should be "Reload from Metadata" and "Save to Metadata" buttons like in Premiere - it would save a lot of confusion and wasted time.)