There are two key differences here that you can rely on
That said, I do like the design of the poster cards and the Brothers Hildebrandt art is all fantastic as is to be expected from them, but Id advise buying the ones you want as singles
Simic Ouroboroid (7 players) : With Llanowar Elves, Gene Pollinator, and Badgermole Cub accelerating its early turns, this deck floods the battlefield with cheap creatures while ramping into an Ouroboroid
Which ones we chose was partially based on what could conceivably exist on Kaladesh, but also on trying to find things that some subset of players would be happy with
Since you get to choose what card you discard, you can get rid of a GX or EX Pokemon in your hand, so there's no risk of it getting knocked out on the Bench, and Mewtwo and Mew-GX can take advantage of its attacks