M785s – loads of power, never found them on/off but I’m 100kg so could be a factor, reliable and easy to bleed
M8000s – avoid unless you get the levers with NK on the sticker. Apparently this is the batch that have been tested and won’t pump up. Scary that Shimano don’t test all their kit. When they work, awesome, power + control. If not, bite point is a gamble.
Zees – early days, feel less ‘solid’ when using resin pads compared to metal pads in XTs but seem to have plenty of power. Would prefer metal pads + the tool free lever adjust, bite adjust, proper pad bolts not split pins but the latter points are more to do with working on them than riding.
HTH