I've gotten to ride all of those, but only on demo bikes (which for the most part were larger bikes). If given the option I'd only ever ride Saints (or Saint calipers and XTR levers on both ends), because I adapted to those brakes almost instantly. They're unequivocally better, I just can't bring myself to spend more than I spent on M785 XT's
The servo wave nature on the XT/SLX/Deore brakes to most feels really on-off, but to me I feel like it's just a steeply ramped spline area where I'm trying to do all my modulation work with the finger within 3-5mm of lever travel. While not ideal, I've just gotten used to it - every brake I had ridden before moving to XT/SLX was garbage (Formula R1 & T1, Tektro cable-disks, and Avid Elixir 1's)...
but a grain of salt is still required because my other bike that sees the most miles is still running Elixir 1's on small rotors. Despite the practically worthless tires I run on that bike (utterly worn out Maxxis Aspen's - semi-slicks, but anymore the 'semi' is in name only), I'm pushing the thermal envelope on those brakes anyway.
So- I tend to be pretty indifferent about brakes provided I can get enough power to overwhelm the tires