I will start by saying that I am a big fan of cosmic settings in superhero comics. Very few product lines seem to have tapped into the vein of the genre quite as nicely as ION Guard. continuing with the simple yet elegant feel of the ICONs rpg, this book successfully presents the genre it represents as well as offering players and GMs plenty to work with to make a successful campaign.
One of the particular strengths of this supplement is its ability to present enough information on the setting to make it vivid while maintaining a healthy respect for the broad concepts of the genre. This allows players and GMs to know where they are and what they should be doing while also allowing them plenty of room to make the universe their own.