Grand Rapids flyboys Mustard Plug survived the great late-'90s commercial ska explosion, and all they got was a lousy touring van and a small but devoted following. Frantic guitar upstrokes, '50s crooner sensibilities, a dash of punk vitriol, and a reggae-influenced rhythm section remain intact, and the music has retained a certain purity. No pop-punk mainstream concessions, no overblown MTV exposure, and no airplay. Though it doesn't necessarily add anything new to ska's hyper-repetitious repertoire, Mustard Plug's sheer existence hearkens to a simpler time in the genre's history. All the historical touchstones are here: a self-financed demo cassette christened with a terrible ska-play-on-words title (1992's Skapocalypse Now!); a prominent, much-revered debut CD for cult ska label Moon Records (1993's Big Daddy Multitude); a goofy-yet-endearing cover tune that supplied the band with its closest brush with fame (a rousing version of "The Freshman" by the Verve Pipe); and various fleeting brushes with rock royalty (Weird Al Yankovic, schizophrenic cult icon Wesley Willis). In ska, history counts for more than your personal identity, so while Mustard Plug's third full-length, Pray for Mojo, manages some slick grooves and rousing sing-along anthems, it underscores the idea that ska's reliance on familiarity, repetition, and tradition makes the compilation disc the ideal format to enjoy it. Thus, it soldiers on -- energetic, fan-friendly, and reliant upon a beat-up van.