The book is officially a YA PA, but I'd position it more toward a teenage age group. 
 The story kicks off with a classic "MC wakes up without memories" setup and finds himself in a teenage boy group in a strange environment, where nobody knows how they'd got there and why. 
 The environment they live in is interesting and many details, usually overlooked, are handled. The story has a good arc and a good finish that opens up the next book but without too many cliffhangers. 
 To make it "school compatible", the author chose a funny way to replace "the F words and SH words" :) 
 What I liked: 
 - In terms of boys' group, it's a modern setup of some classic child fiction. 
 - Nice arc from "peaceful survival life" to "speed up survival game". 
 What I did not like: 
 - The way the boys acted, often felt forced and unnatural. Smelling of an adult trying to sound like a 'boy from the block'. 
 - Despite being chosen for their intelligence and will to survive, they'd done little in two years except for gardening and running around like mice. 
 - The grievers and the sheer size of the maze were unrealistic. They fit the story perfectly, but still... 
 - Haven't read the second book, but seems to turn into a more cliche "This is not a zombie apocalypse! Ok, they look like zombies. They act like zombies. But I swear this is not a zombie world!" :) 
 - Two years with a boys only group. A beautiful girl shows up and they just sneer at her? C'mon.... 
 Anyway... I had a longer list of not likes, but it's still definitely worth reading.