I have to admit that I love this game even though have only listened to actual plays and played in a short play by post game. I play Wild Talents quite a bit and it is based on a streamlined version of that system (One Roll Engine). The best part of this book (and the "full sized Monstrous Edition version") is that it is more straightforward and easy to run than Wild Talents. That game has a ton of flexibility like this one, but can be hard to pick up for novices. This game, much like it's premise, is easy to get into and runs smoothly from start to finish.
In a standard game, you get to play as a kid who is friends with a powerful monster. You get into trouble and have outlandish adventures as the monster gets you into sticky situations with adults, kids, and of course other monsters. The rules for creating your kid are very simple. You can roll up your character pretty efficiently before a session. Monsters take a bit more time to tweak their powers and hit locations (think body parts with associated hit points and super powers). However, don't have enough time to put together your monster before an impromptu game? No problem! They included a random monster generation section with plenty of tables to roll that dude up lickety split. That is much appreciated, especially as a GM making monsters for other kids.
You can create kids from small children to adolescents and run just about scenario that they might find themselves in. Arc Dream has several campaign books out including Candlewick Manor and the newly released Road Trip, which provide everything you need to run an extended story with your friends. Those are all written extremely well, well organized, and have beautiful artwork, much like this book. They are also really worth the money.
Speaking of money, at half the price of the Monstrous Edition and including ALL of the same material, this $7.50 PDF should be in absolutely every RPG fan's collection. Of course, I love PDFs because it's just easier than taking the book along everywhere I go. You can bet I'll be running this with my group soon.