Well we have the other apoc warzones released thus far, so don't see any reason not to add it to the collection...
On another note, while I considered the Horus Heresey books to be too big an investment for the club when they were mahoosive tomes at £80 a pop, especially given they were only for the power armour players, NOW that forge world have released a sort of "abridged" version that includes the army lists without all the attendant background and artwork, in two books, each at the price of a standard codex... would anyone be interested in those?