Remember to buy two devices and to swap usage every month. If one breaks you loose access since the keys shouldn't leave the device. Use two and always setup two keys .
Oh and the yubikeys nowdays are closed source. If you want actual open source hardware and software, checkout the Nitrokey Start. It's cheaper and fully open source, hard and software. Its an openpgp token: https://raymii.org/s/articles/Nitrokey_Start_Getting_started...
If you want a smartcard, Nitrokey had Both the pro and the HSM. An openpgp smartcard and and smartcard-hsm (just pkcs#11).
Oh and the yubikeys nowdays are closed source. If you want actual open source hardware and software, checkout the Nitrokey Start. It's cheaper and fully open source, hard and software. Its an openpgp token: https://raymii.org/s/articles/Nitrokey_Start_Getting_started...
If you want a smartcard, Nitrokey had Both the pro and the HSM. An openpgp smartcard and and smartcard-hsm (just pkcs#11).