As for PD15, GTX1060 works great with it. Don't have a 4K camcorder, but I do a lot of 1080p MPEG2 to MP4 TV shows. PD15 can down convert 1080p(8 to 12Mbps depending on channel) to 720p 5Mbps one hour show in less than 6min. usually no editing although sometimes I might trim the beginning some. My previous GPU was ATI R7870 so the difference was VERY significant. PD just seems to have better support for nVidia GPUs.
I have a Sony 3D camcorder, but I haven't gotten into editing in 3D much. I'm the only one in the family with 3D TV LOL Intel i7 4770k, 16GB, GTX1060 3GB, Two 240GB SSD, 4TB HD, Sony HDR-TD20V 3D camcorder, Sony SLT-A65VK for still images, Windows 10 Pro, 64bit
Gary Russell -- TN USA