Sunday Morning Bonus Pulp: Mystery Book Magazine, Summer 1950
"The Best in New Detective Fiction", this cover from MYSTERY BOOK MAGAZINE proclaims, and I think they could make a persuasive argument. Inside this issue are "The Case of the Dancing Sandwiches" by Fredric Brown, also known as one of the famous Dell 10 Cent Books (see below), as well as stories by John D. MacDonald, Philip Ketchum, D.L. Champion (creator of the long-running Phantom Detective series), the house-name John L. Benton, and a couple of authors I've never heard of, Jonathan Joseph and Bryant Ford. I don't know if that's actually the best, but it's pretty darned good.