It’s not bad, not by any stretch. Really, it’s quite entertaining. Michael Cera actually pushes a bit beyond his comfortable familiar box (not a lot, but a bit); all of the performances are clever and fun, the gags all work even if a few are groaners (“bi-furious” still makes me wince), the action is decent, and most of the plot chunks that were removed from the comic (Stills’ coming out, for example) aren’t really necessary to drive the movie.
But – I know it’s a cliche to say “the book was better,” but, well, the books were better. The books form a story about the often painful transition to adulthood; although elements of that are still in the script, it almost seems perfunctory, in a “hey [character], I was totally a douche but now we’re cool right” sense. You kind of wonder if the seemingly inevitable director’s cut will focus on that more.
Also, losing the Honest Ed’s chase battle sequence is heresy.