see how it goes, maybe you won't even feel that you need it this time - you never know. if this dc is not back to back (hopefully) it may be a lot easier?
i had epidural with my first, who was also back to back (and induced, v long labour) it was a quite difficult birth and i felt like really needed the epidural and i felt that in the future i would always want one because couldn't imagine coping without.
however ds2 i didnt have it, just gas and air and actually it was fine much much easier than expected and was so glad i never had epidural with him in the end.
i did actually ask for it as i kind of felt as though i "should" ask but i was asking quite half heartedly i think? and they didn't bring it for me as i was nearly @ the pushing stage by that time so the midwife felt it would really slow things down.
afterwards she said to me that she hoped i did not mind about not getting the epidural as i would have been there for hours more had i got it, i actually thanked her for not giving me it. and felt such a sense of accomplishment that i had him without the epidural because of how much i thought before that i would have to rely on it.
the crowning and everything was much less painful than i expected, although i was high on gas and air which i think helps a LOT otherwise probably would have hurt like hell, but overall i was so suprised how easy it was compared with my 1st and that really i did not need the epidural at all. was much quicker too so i think that makes it easier to cope though
with it being dc3 maybe yours will be quite quick? hopefully...
but if it is back to back again i would keep ur options open for an epidural because it can be really difficult, and if you feel you need it i wouldnt deny yourself. so just see how you get on?