Hi Ron,
With LG displays you will never get a viable calibration without the use of a 3D LUT.
But, there are few 4K LUT boxes available, with the FSI BoxIO being the only really viable one.
See:
http://www.lightillusion.com/boxio_lut_box.htmlThis really means using the output LUT capability of resolve would be an obvious way to perform the calibration, as many users do already.
As for the actual calibration - Rec709, or DCI P3, you really need to profile the display with a suitable probe and LightSpace CMS to see what it is really capable of, and then define your best workflow.
If the display really can get close to 100% P3, that may be viable.
But, a Rec709 calibration, with a LUT to convert to P3 after the work will always be 100% accurate.
I hope that helps.
Steve
Steve Shaw
Mob Boss at Light Illusion