Poll: Would you use a hosted authentication solution like Auth0?

On one hand, many frameworks either have authentication bundled in (Django) or it's relatively easy to add (Rails & Devise). It's also scary to think that the service might disappear one day (Stormpath was just acquired by Okta.)

On the other, the gold standard for auth has become a bit of a hassle (OAuth, 2 Factor, watching leak lists, etc).

Does anyone know of an open source authentication microservice that works like these hosted solutions?