Hi @Bigtodd, i’m also interested and wonder about cross compatibility. I have the Border Flak 36 model kit, and I also have the Voyager Flak kit… but the Voyager set I have is for the Dragon model kit not my Border version 
Surely they would be cross compatible on the most part…. that’s what i’m hoping is the case…. but as @varanusk says… with good planning you shouldn’t need to worry if you buy the right Voyager version for your needs!