Adobe does offer information on GoPro Cineform in Help and especially on blog posts, but render quality settings are a little less mysterious if you visit the Cineform forum. Still, some questions remain even after exploring other resources.
Read the rest at PVC in Cineform in Creative Cloud: render quality settings + more.
Note that it includes recent clarifications from Adobe.
In tests here, the important takeaway is that
the higher quality options seem to produce smaller files than the lower