Bug Boys: Outside and Beyond gets trippy and philosophical and breaks the 4th wall often! But I enjoyed  it just as much as the first book. Stag-B and Rhino-B are still as adorable as ever. The artwork is oh-so lovely with green foliage and cartoony expressions. 

I would recommend this for middle grade readers because some of the more philosophical bits may confuse younger kids (but also an opportunity to create discussion). Also, Stag-B’s insecurities about his friend growing up faster than him will probably resonate more with middle grade readers because they’re in a transitory period.