Author of Epf here. We had used Ember data for over a year before creating and switching to Epf.
Epf was heavily inspired (if not directly based on) many parts of Ember Data. We felt that Ember Data provided the right level of abstraction, but fell short and created road blocks for us in certain scenarios.
I've been using Ember-data for the past few months on side projects and it's getting a lot more stable. I've rarely had issues with it in the past few weeks.
"weeks" ??
Damn... I remember when I had to choose between angularJs and other JS frameworks a few months ago. Reading your comment makes me feel really good with my choice.
I've played around with Angular quite a bit lately as well and I definitely prefer Ember. You should really try both of them out and give them both a fair chance.
Also, you don't have to use data with Ember, it's just a benefit.
Last time I used it, I think it was Revision 11, it had issues with relationships and deletions, how is it holding up now? I'd love to give it another go!
There are still issues on rev13. For example, when binding to the didCreate event after committing a model, the model.id is not defined. You would think `didCreate`, fired when a response is returned from the server, and that response includes the complete model including the ID, your client-side model would now include the ID as well. Not so! You have to do tricks like `model.addObserver('id')` to get what you need.
Ember.js is great fun, until it goes horribly wrong. On the other hand, the Ember Core team does not call it a 1.0 — and they certainly do not say Ember Data is finished. I think it's unfair to judge such early builds.
Epf was heavily inspired (if not directly based on) many parts of Ember Data. We felt that Ember Data provided the right level of abstraction, but fell short and created road blocks for us in certain scenarios.