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Bruno Mars and Justin Bieber aren't just multi-platinum singers - they're also snappy dressers.  Both stars are among the musicians who've made GQ's list of the 30 Most Stylish Young Men in Hollywood, along with Joe Jonas, Nick Jonas and"Glee's" Darren Criss, who actually topped the list.

The magazine calls Bruno, who came in at #30 on the list, "a master of throwback style," saying he's "one part Elvis, one part Sinatra, one part R&B charmer."  As for the Bieb, in at #9, the magazine says, "His taste is about as lux as you can get: YSL brooches, Watanabe varsity jackets [and] custom-made motorcycle jackets in powder blue."  GQ also notes, "Sure, he has the occasional miss, but he's mopping the floor with most other kids who just exited puberty."

Nick Jonas is #6 on the list, and GQ says he "looks like a movie star" with his "leather jackets and slinky tees."  His bro Joe is #4, and the mag hails him for being an "early adopter of the jean-jacket-under-a-blazer thing that's blowing up."  They also give him props for rocking "the gutsiest suits on the planet: white, plaid, purple striped - you name it."

As for #1 stunner Darren Criss, GQ says, "No one comes correct and with more variety…Bow ties, trim suits in gutsy shades, saddle shoes, smart casual attire-there's no look or flourish he can't pull off."

The most unusual person to end up on the list, though, is Gwen Stefani's son, Kingston Rossdale.  Yeah, he's under 30, all right - he's not even six-years-old. Still, the magazine raves about his look, which isn't surprising given that his mom's a part-time fashion designer and his dad Gavin Rossdale's no slouch in the style department either.  "Look at this kid!" says GQ.  "This rock scion obviously has a leg up on all the other boys in the, er, playground.  Expect him to occupy this list for, oh, the next 24 years or so."