I used Adobe CS6 with Cineform, using an of the shelve HP Envy 14 laptop.
(12GB RAM with Intel 5000 Graphic Card)

1. The video capture format was set to 3480p, with simultaneous 720p recording.
2. Sony Play Memories software to transfer files to the computer.
3. In Premiere CS6 I edited the 720p footage. (No problems, very smooth)
4. After editing I swapped the edited 720p clips out for the 3480p clips.
5. Exported to a Cineform 3480p file.
(Exporting by handing it over to the Media Encoder did not work, only the audio would export)
Direct from the timeline within Premiere it worked fine (also fast)
6. I dropped the finished video in the Media Encoder on a Vimeo HD 1080p preset.

You can go to my Youtube Page for the video

Flagstaff - YouTube

With a Premiere compatible graphics card the 3840p edits smoothly, with no intermediate. This is on a MacBook Pro, and on a Mac Pro. I export the final video to a high bitrate H.264.

I do like to export to Cineform if I use AE, and then take this into Premiere.

Edius 7 will edit smoothly full frame rate with native clips on a 3840x2160 timeline or a 1920x1080 timeline for direct output to whatever. My system has no separate GPU card just the Intel onboard GPU. Edius doesn't use the GPU unless some of the GPU driven filters are used. It is an Intel i7 4790K at 4Mhz running Windows 7, 16G RAM Gigabyte motherboard and about 8T of hard drives.

Edit with native clips and output to whatever format is needed from the timeline.

Ron Evans