A while ago I noted that FCP X was faster editing 4K material on a 2014 MBP and GT 750M GPU vs. Premiere Pro CC 2015 (latest) on a 12 Core MacPro and GTX 980ti. Today I tried FCP X on the MacPro in FCP X with C300 II 4K files. 4K editing was blazing fast- scrubbing instantaneously. This is full 4K resolution, native files (dual 4K displays). Curious to find the limit, I began stacking 4K clips and was able to get 6 4K clips (cropped so all 6 clips had visible elements) before there was visible s