Had the chance to try out the RX0 against some... or with some fire dancers.
Have not yet cracked the colour grading - but I got to say, I am impressed with how the slow-motion renders flame. (Slow motion filmed at 1000-1200 iso, 240 fps, played back at 25 fps) Regular shots are filmed at 300-400 iso, 25 fps. All at F4.
Slow-motion upscaled to 1080 using Instant 4k from Red Giant.
Happy to share/ set up