"Ain't no going back now," sings Australian triple threat Iggy Azalea on the majestic opening track of the emphatically titled The New Classic. It's a good thing the rapper/singer/model has such resolve; her debut album faced long delays as she navigated the major-label maze. Having finally arrived, it posits Azalea as pop-hop's latest superstar: a nimble, catty rapper who sounds perfectly at home amid a panoply of club-destined bangers. Helmed by a who's-who of in-demand producers (The Invisible Men, The Messengers, Stargate), The New Classic is impossibly sleek, its beats revved up and zooming like a Ferrari down Rodeo Drive. "100," a slinking guitar groove produced by and featuring the Atlanta trap trio Watch the Duck, includes Azalea running down her shopping list: "No Michael Kors, just Tom Ford." She invites haters to "walk a mile in these Louboutins" on "Work," a trap anthem that describes Azalea's hardscrabble background: "Sixteen in the middle of Miami, no money, no family." Clearly she's come a long way.