I have used them (coincidentally, with Okta), and they are pretty neat! I actually choose to use them instead of a smartphone app where I can, because it's much faster to use. I'd recommend them to companies as a good measure.
They are still effectively 2FA where it's just a lot harder to work out the proprietary system with which the password is encoded. So it is a sort of a 'security by obscurity', but the likelihood of someone going through all the work to disassemble your key and work it out with you noticing / before the key gets invalidated is pretty low, so unless you're protecting something super-duper high value (and assuming the manufacturer hasn't screwed up too badly), they'll do a good job.
I have used them (coincidentally, with Okta), and they are pretty neat! I actually choose to use them instead of a smartphone app where I can, because it's much faster to use. I'd recommend them to companies as a good measure.
They are still effectively 2FA where it's just a lot harder to work out the proprietary system with which the password is encoded. So it is a sort of a 'security by obscurity', but the likelihood of someone going through all the work to disassemble your key and work it out with you noticing / before the key gets invalidated is pretty low, so unless you're protecting something super-duper high value (and assuming the manufacturer hasn't screwed up too badly), they'll do a good job.