Ember data docs are pretty sparse, but once you get up and going, the learning curve is pretty flat. Backbone is pretty easy to get going, but the code complexity gets exponential when you have lots of collections and references that need to be updated.

It's easy to get frustrated with ember & ember-data and just jump ship to backbone, but you'll be paying for it later when your data model expands beyond 5 interconnected models.

The best advice is to tough it out with ember even if the docs are weak and tutorials are sparse.