I took HF final exam today and felt that was not tough. I am still not confident about real exam.
Well, you can be confident about the real exam then! Head First EJB's final mock exam is very comparable to the real exam as far as its contents and level of difficulty are concerned. But as it doesn't mention the number of correct answers (contrary to the real one), the mock exam is more difficult. I personally got a better score (+/- 10% if I remember well) on the real one.