darco wrote:
Yubico Authenticator supports both event-based (HOTP) and time-based (TOTP) credentials, as does Google Authenticator, so this isn't really a differentiator as long as you have a good password on your YubiOATH app.
Adding to darco's answer, the majority of services online use TOTP, so you cannot generate OTPs in advance unless you have access to the secret and know the time you want the OTP for (typically a 30 second window, with the server making some allowance for entry time and clock skew).
I have credentials for Google, Microsoft, Dropbox, Facebook, Tumblr and github on my Yubikey Neo. All are TOTP credentials.
The only event-based credentials I have are those I use with the Yubikey's 'touch button' capabilities: Yubico OTP (which I don't use much) and Symantec VIP (which I use with PayPal). I also have event based hardware OTP setups from two UK banks - HSBC uses a self-contained PIN protected token and Nationwide use a small device that works with the
Chip Authentication Program feature on their cards.