Thanks for all the advice so far!

I should clarify a couple of points: the wedding is at 7PM in a well-lit formal garden (the groom, his father, and the groomsmen will be in tuxes) so I thought that the PC would be most appropriate. Also, the younger daughter has no wedding plans as yet, but tends to be more formal than her sister- so my thought is that her wedding will probably be more elaborate as well, and that a PC will be appropriate at that time.