I am unfamiliar with this series. Are there any "must haves?"Any recommendations?
Can't help you there. I never understood the FL excitement at introduction. If you like apocalysm by Collins, buy his volumes. If you like Bonhaufer (sp), buy him. Some are unique in Logos ... church architecture.
Yes! Definitely worth it. You don't need all of them, but they are incredibly detailed, ecumenical, and enjoyable to read. If anything, the bibliographies and suggested readings at the end of each chapter are worth it. If you have the money, buy all of them since the discount is better than even the pre-pub discount. If you can only buy a few, buy the ones that interest you the most.
My must haves were: Biblical Studies, Bible in America, Early Christian Ritual, Archaeology, and Biblical Narrative. The shear breadth of each is astounding. I ended up buying all of them after reading a few chapters of the Biblical Studies one.