Also, if you read Howard Hall's Lembeh report, his Red One actually melted, I suppose as heat built up in the housing during those super-long Lembeh dives. I've no idea if the more recent Reds run cooler, or whether housing design can somehow cater for it, but it's worth bearing in mind.
RED are claiming that the Scarlet runs a lot cooler than EPIC or the RED ONE. I'm not entirely sure why it would run cooler than the EPIC at the same res/frame rate, so perhaps it is just that you can't work it as hard with overcranking etc. With regard to HH melting his RED ONE at Lembeh then I'm sure a few Sony's and Canon's have also melted there over the years! I know I was pushing my kit to the limit with 3x2 hour dives a day