I am going to go back to the beginning..
what is your deliverable? this sounds as if you are new to the DPX / 4:4:4 requirement and needs.
In my experience 80% of users are fine Keying out from ProRes or 10bit UC footage rather than going the DPX route. I would not recommend the complexity of the DPX workflow for a new user without first testing on a small project, do to the shear number of files that need to be created and kept track of when you realize you are creating 86,400 files for every hour of content
did i mention that those frames in 2K are about 8MBs and at 4K they are 48 MBs EACH
gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Inside look at the IoHD