It's no insult to point out that country music radio confectioners Sugarland are about as pop as country comes. That's pop as it used to be: melodically unfussy, equal parts candy and substance. They'll na na na pleasantly as a track fades out, and, Christ, the duo wraps up the "fan club edition" of their likable Love on the Inside disc with a live cover of "Life in a Northern Town." Strip out Jennifer Nettles' tart twang, and the group's sparkling recent No. 1 "All I Want to Do" could have held court on Casey Kasem's Top 40 anytime in the '80s. Same goes for current chart-topper "It Happens," a riffy new-wave number that cross-pollinates "9 to 5" with the Stray Cats. Of course, stripping out Nettles would be a mistake — she's got the sun in her voice, just as it's in partner Kristian Bush's strumming on all four of Sugarland's big hits.