I used Rails 3.2 and Sails 0.12 in the past.
The lifecycle callback methods are almost identical to Rails. Waterline is an absolutely awful ORM for database management: You have almost no granular control over joins on MySQL tables. Additionally, the third-party libraries available for Node.js are much more sparse than the Rails' ecosystem.
Having said all of this, I am still very excited to upgrade my Sails API to 1.0 and take advantage of all of the new ES6 features.