Intresting, what about moisture resistence? Because in the past I've heard some of those performance brake fluids didn't hold up well to time and changing temperature conditions so they weren't ideal for long term in daily drivers. I've tracked ATE fluids a lot in my m3 and it always seemed great, but I don't doubt there's better.
I like motul products, used them before in bikes with excellent results just curious. You say it's better cause of a higher boiling point?
What you are thinking of is the wet boiling point. And that is actually where ATE fell on its face, take a look at the difference between its wet and dry boiling points, then look at motul RBF600 and 660. There is more to the formula than this, but a good test is to take the difference between the wet and dry boiling points, divide that by 2 and add it to the wet boiling point. That will give a more realistic number for your use.
So using that, really quickly...
Motul RBF600 True Boiling - 507*F (this is still the winner given how close it is to the 660 and it having a MUCH higher full wet boiling point)
Motul RBF660 True Boiling - 508*F
ATE Super Blue True Boiling - 462*F
AP Racing True Boiling - 445*F