Setting up passwordless sudo with Yubikey

YubiKey seems popular, but with all the big brains here, how good are the alternatives?

OnlyKey seems too good to be true, is it?

for sudo and libpam like they are doing in that post, a fingerprint reader is even better. same HSM, but one extra layer of security.

Setting up passwordless sudo with Yubikey (zackproser.com)