I basically grilled my ND/birth attendant about forceps/vacuum. While they do homebirth, they are licensed by the state to use ve.
she told me: VE can be used as high up as forceps, however, since you don't have to get the pincers around the baby's head, between the vag and the head, it can be more effective than forceps if the baby is tightly "wedged" in the vagina. she also said she never used them. even tho they bring them.
i agree with blueviolet that jus cuz you're fully efaced and at 10cm or whatever, you may not be ready to push. Odent describs this in one of his books. Acording to Odent, some women at his birthing center in France will wait between the final expansion/efacement of the cervix and the beginng of the pushing phase - this is what he called transition, so I got confused when some folks called pushing or the last few cenimeters of dialation transition. Anyway, at his center, they never encouraged women to push before their body felt the urge to push. No EFM, just occasional checking. In some cases the baby would get all the way to the opening of vagina before feeling anything, instead of having the mom [forcibly] pushing the baby all the way from the uterus, down the vagina, twisting thru the pelvic inlet and outlet to the opening. He also suggested this interlude between contracting the cervix and pushing the baby out was a sort of break for the mom, esp if she was tired from dealing with the contractions to open the cervix. I think this might be mentioned in Gentle Birth Choices or Choosing Waterbirth - but it was attributed to Michael Odent's comments and clincial data.