I get that that is an older book, but if I had won that I would have posted it here too. Being from one of the big Atlas/Marvel pre-hero titles, and one of the longest running, it can be hard to know where the cutoff is (I sure don't). I like to see those types of books here, and looking back through this thread's history you see plenty of them. They fall through the crack between GA and SA for me. (I guess they are technically Atom Age?) Atlas books from this era have always felt like early SA to me, even though I know that technically they aren't.
Now if it had been Mystic or Astonishing or one of those titles that never led to a hero book that is an easy call. But to me, wrong or right, JIM is a Marvel pre-hero book because it eventually gave rise to a hero. This may be a creative interpretation of the thread title and rules, but that is just how I have always seen it. I realize that many will probably disagree with me on this, and I am happy to be educated on the nuances of the ages and designations.
I define a "pre-hero" as any book from the late 50s-early 60s that contains fantasy stories by Kirby, Ditko, and/or Heck. Titles that dont lead directly to a hero -Strange Worlds & World of Fantasy - are considered "pre-hero" based on their content. Titles like Jounrey Into Unknown Worlds or Strange Tales of the Unusual are not pre-hero, because they dont have any Kirby/Ditko/Heck stories.
Now, I would also lump the "early-hero" books into the pre-hero classification as they do contain fantasy stories by K-D-H. For example, even though the Torch takes over Strange Tales, those books still contain some great (and overlooked) fantasy backup stories that would fit right into the early pre-hero era.