Good luck! A couple of babies ago, I had a sweep at 39w when I was 3 cm and very soft; baby was born within 24 hours.
My ob's office is usually pretty firm about not doing sweeps until at least 39w. My appt this week is at 38w5d, so we'll see what he says... I'm getting anxious to get this baby out; I'm just afraid there's a problem (there is no evidence of one though).