Have Epi is to numb your lower body so that you will not feel the pain during contractions as well as when pushing baby out (for natural). It will set your bill back by a few hundreds $. After Epi, need to take care of your back else may have backache years later.
Without Epi, can feel the whole process during the labour to giving birth (natural). Save some money on the bill.
That's all I knew. Other mummies can better advise you.