Setting up Duo Security and having to track (yet another) account is a hassle to get 2FA. I also find the per-account setup process and UI to be fairly cumbersome. If Google Apps SSO ( https://big.ideas.aha.io/ideas/APP-I-513 ) isn't on the cards, I'd much prefer to be able to add Aha to the Google Authenticator app, which I already use for other apps.
Now that Google SSO is supported (https://big.ideas.aha.io/ideas/APP-I-513) you can use Google two-factor authentication via Google SSO.