I downloaded the three output transform candidates and have been comparing them here and there using old renders and in current projects. They are all quite a bit dialed down from ultra-punchy ACES 1.2! My feeling so far is that Candidate A is a nice “clean slate” and C is a “finished render” option that would require only minimal grading after rendering. I found that B was a bit saturated in some areas and didn’t feel like a general purpose, neutral choice.
Here’s the difference I noticed between B and C. It was particularly clear in this metal material. B comes out a bit orange, which isn’t present in any other output transform and I don’t think accurately represents the colors chosen when the render was set up.