Ember.js or Backbone.js with Rails?

Ember is a lot nicer. If I had to sum it up in one sentence: More features that make life easier for the developer. If you are coming from Rails you'll agree with a lot of the choices behind the project. By that I mean the whole idea that convention is better than configuration, as long as there is an easy way to change that convention if need be.

In the last year I built three JS applications of various sizes. Two were in Backbone and the third was done in Ember. I really have nothing bad to say about Backbone, but I'll probably never go back to it again. Writing in Ember just felt great. I didn't really have to think about MVC or how I would design certain patterns because Ember supplied all of that to much. This made the project very easy to deal with when it was starting out and small, but also made things really easy when refactoring and as the started to grow in size.

Prototype something in Ember.js first.

Is there anything you would change? If there is, you should remember that Ember.js is a very convention-over-configuration heavy framework.

Ember.js will do work for you, and if you agree with how it does that, it will be less boilerplate than using Backbone.js.

Backbone.js, on the other hand let's you structure code however you like.

Personal opinion: I prefer Backbone.js for my projects.

What is your level of understanding of the philosophy behind either framework?