I've worked on storage drivers for Linux (2.6), Mac (10.6+ - 10.8) and Windows.
What like Nt vs Zw? Are you fucking serious? Do I need a badge and certification from you too, your majesty? You haven't proven you've done shit either, but it doesn't matter.
You don't have experience with xnu kexts (which make much more sense, at least more so than the Linux model), so I don't see how you can claim, broad pseudo-expert "opinion" on something you know nothing about.
Regardless, these three approaches are still irrelevant because they're critically flawed: granting transfinite trust to the kernel driver developer to not fuck up. A real microkernel model, only a process would likely crash. QNX runs on billions of devices, including now BlackBerry 10 since they acquired it: game, set, match.
That's the boat you've missed trying to go off into the weeds and make it a personal attack, because you have nothing.