I'm an EasyMock developer so a bit partial but of course I've used EasyMock on large scale projects.
My opinion is that EasyMock tests will indeed breaks once in a while. EasyMock forces you to do a complete recording of what you expect. This requires some discipline. You should really record what is expected not what the tested method currently needs. For instance, if it doesn't matter how many time a method is called on a mock, don't be afraid of using andStubReturn. Also, if you don't care about a parameter, use anyObject() and so on. Thinking in TDD can help on that.
My analyze is that EasyMock tests will break more often but Mockito ones won't when you would want them to. I prefer my tests to break. At least I'm aware of what was the impacts of my development. This is of course, my personal point of view.
