Final Cut Pro X & Davinci Resolve workflow
What I'd do:


Duplicate the project for a backup.
"Collapse" the timeline from the bottom up:  Lasso all of the clips
immediately above the primary storyline (to make a Premiere
analogy, if the primary storyline is V1, then select all of the
clips on V2), right click, and select "overwrite to primary
storyline."
Repeat step 2 until there are no clips above the primary storyline.
File->Export XML
Import this xml file into Resolve
Color clips
Render individual source files
Replace FCPX clips with new ones


I don't have my DaVinci Dongle on me, or I'd elaborate on that side.