Thanks for commenting on my post @reC.
Regarding speed, the CPU of the Librem 14 has been benchmarked indeed and in my experience, those benchmarks are pretty reliable when it comes to pure CPU processing (like rendering a video or an image sequence in my daily usage).
Regarding calibration, I have to admit that I never used a calibration device. I don’t do digital painting and for grading my images and videos I always rely on the graphs instead of my eyes. Even with the best calibrated monitor, my eyes cannot tell me what’s pure black or pure white, which is my reference when grading.