FIXTURES using reopenClass or not

Ember Data
1

Given a model called Post, I would like to know what’s the difference, advantages and disadvantages of using either:

Post.FIXTURES = [
  ...
];

or

Post.reopenClass({
  FIXTURES: [
    ...
  ]
});
2

When model injection is enabled you have to use reopenClass.

3

Never realized this. Good one, thanks.