I HIGHLY recommend you use a paci from day one!
I made the mistake of wating and I ended up being the paci! All of my BF babies had to nurse on me to fall asleep, it's a BAD habit to break and so easy to fall into. IF I had started them with a paci from day one, they would have easily fallen asleep on their own (like my bottle fed baby did).
There's even new research out that says paci's "help" in preventing SIDS because the sucking of the paci keeps baby from falling into a deep sleep which helps prevent SIDS. It was something I heard on the news a few years ago.
But again, I don't think your baby will NOT nurse because of the paci, if anything it will only take you and not the paci but it's GREAT if they take the paci and will make car rides much much smoother. My one child that took the paci was always so much calmer and quieter when we went places (if he had his paci) and although many have trouble getting rid of the paci, it wasn't hard for us. The older he got the more he understood he was growing up and didn't need the paci anymore.
Good luck to you!