Protection is key for me.
Thus, I choose a boot with a HINGED ANKLE JOINT. My nomenclature may be incorrect, but . . . the boot has a fixed hinge at the ankle bend, providing stability in the event of a crash.
Not to push any particular brand, SIDI Adventure Rain Boots fit my requirements. Newer models exist; mine are "waterproof" with a proprietary liner; Goretex-lined models are available.
Do they work? Yes, in several crashes, at various speeds, on several surfaces from soft mud to hard pavement. Waterproof? Yes, externally, but . . . if you get into depth beyond the boot top, it will take FOREVER to dry the boots out!
If you're going SIDI, in the US, anyway; BRING MONEY! Some save by buying on-line from Europe, but looks like that trick takes some finesse and time.