Phil Guie of Pop Culture Shock commended the illustrator for capturing the protagonist's "childlike enthusiasm for old monster movies perfectly with lots of full-page panels"[23] and commented that "the creative team also seems to understand that a hero is only as good as his nemesis".[24] Sam Kusek from Pop Culture Shock commended the manga for making "a very nice reference to The Sound of Music".[25]
Manga Life's Barb Lien-Cooper criticized the manga for using movie special effects that "don't translate onto paper".[26] About.com's Deb Aoki commended the manga for featuring "a high-spirited, smart and likeable hero with an unusual profession" but she also criticized the manga for minimal character development and "one-dimensional villains".[27]
Comics Worth Reading's Johanna Draper Carlson commented that "the transformation process is a chance for dramatic art. It's treated intensely, as though it were life-saving surgery, but with the elements and techniques explained to the reader, providing a mini-course in movie makeup".[28] A later review by Carlson commented that "many of Kohei's effects serve no purpose in the bigger story beyond entertaining the reader".[29] Active Anime's Davey C. Jones commented that the manga "keeps the action hoppin' and the mysteries boppin'!"[30]
Coolstreak Comics' Leroy Douresseaux commented that the "action can get pretty intense at times, but never more than anything one would find in a PG-13-rated movie".[31] Douresseaux compared Gimmick! to Case Closed and MacGyver.[32][33] A later review by Douresseaux commented on "the stories [which] are full of tidbits on special makeup effects and animatronics, the kind of technical details that give stories realism and also intrigue readers".[34]
Jason Thompson's appendix to Manga: The Complete Guide commended the manga for its "basic shonen story structure with the mysterious mentor and the 'ambitious, hardworking person who is ridiculously good at some skill/job/ability'".[1] He also commented on the manga's "cinematic leanings are so distinctly Hollywood-focused, which is questionable in one sense (it'd be nice to know more about the history of Japanese special effects), but on the other sense, makes it easy for a Western reader to follow".[1]
Manga Life's Ysabet Reinhardt MacFarlane appreciated the "real-world references" in the manga "primarily to director Sam Raimi's work".[35]