Kate Upton & Chrissy Teigen Prep for a Wild Trip to Vegas

02/13/2013 at 04:00 PM EST

Viva Las Vegas!

Chrissy Teigen, 27, and Sports Illustrated Swimsuit cover girl Kate Upton, 20, were joined by a slew of fellow models who traveled from Newark, N.J., to Sin City recently, and the ladies gave PEOPLE.com a behind-the-scenes look at their trip-planning.

"I just thought I'd show you what's in my purse, because it's kind of fascinating, actually," Teigen said, while pulling out several bags of hair extensions. "I have multitudes of hair."

But as John Legend's fiancée points out, the "creme de la creme" of her handbag contents were yet to come.

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"I have an entire Nintendo 64 in my purse," Teigen said with a laugh, pulling out the clunky entertainment system. "Kate Upton, I am the best Mario Kart player in the world. I'm older than you. I've had much more experience than you, and I dare you to beat me at Mario Kart."

But once the ladies boarded the flight, video games were far from anyone's minds.

"As you can see, the drinks are being served already, which isn't the exact same thing that would happen on a normal flight," Teigen says in her seat before takeoff.

"They're going back and forth. We're having a good time. I don't plan on watching any in-flight video. I think we'll just have a good time, so we'll see what happens. It should be a lot of fun. I'm excited."

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