"Entertainment Weekly" editor Natasha Stovall highlighted the album's different approach, stating that although the "neo-Go-Go's vibe" of songs like "Livin' Large" and "Little One" can be disappointing "for those addicted to the ultra-macha-punk throb of L7 watersheds", "Slap-Happy"s "harmonious pop sweetness" has "a super-catchy, Joan Jett-meets-the-Breeders feel that zestfully floors the accelerator." Jason Hardy of "Daily Nebraskan" stated similar pros, noting that the album's new style introduced a "groovy" side of L7 that "most probably didn't know existed." AllMusic's Stephen Thomas Erlewine described the album as "a respectable but predictable effort", stating that it "leaves very little lasting impression" even though "a few of the songs hit hard, and the band sounds energetic and muscular."