Pro - my cousin who is a florist has one that she rents out, so we're using that one. It's a square box that has space for an 8x10 photo on each side, attached to a pedestal. I like that it's big and not something that people can easily walk off with. And, it locks.
DIY. I had originally planned to use whatever the venue provided but, recently my boss gifted me a gorgeous white wooden box that has a space on the sides for photographs. He suggested putting our engagement photos in it and using it for our card box. I loved the idea and will be DIY-ing a vinyl monogram for the lid to dress it up a bit.