You should do what your common sense tells you to do. Is the money better spent on some photos or something else? Only you know. having had kids, who are now adults, I never wished for the best and prepared for the worst until they were in the cradle. That's just me though.
I never had or wanted one actually but that me! I didn't want the surprise of how my baby looked spoilt, I wanted to see their little faces when they were born.
I am sure plenty of people disagree though and think they are great! I hope your baby behaves and you get good pics!