RED Scarlet-X is a fantastic camera, if you know how to use it. I haven't shot with BMPCC 6K, so I can't do direct comparison, but I think Blackmagic is good too, because they are used a lot.
- very nice skin tone reproduction, if you use IR CUT filter all the time.
- base EI is 800 ASA, in low light you can really push it just to 1280 ASA
- DR is about 13.5 stops (just my rough guessing), not as good as Alexa, but nice
- very good colours, true but organic at the same time
- excellent data with 16 bit depth, but compressed so you don't need that much hard drives
Scarlet is fantastic for people, who know how to shoot, who know how to light the scene, who use it as a proper film camera.