I don’t know about 1017 but according to my limited testing of 0910 and previous v4-flash-0731 on some of my use cases, max simply used a lot more tokens (almost twice as many IIRC) for little to no benefit over high. So yeah I really don’t see a reason to use max.
And not only your testing, I have seen that claim a lot of time online. I never tested it, though.