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Spencer and Heidi Pratt are thrilled at the news that Kristin Cavallari will be replacing Lauren Conrad on MTV's The Hills.

"I love Kristin. She introduced us," Heidi told Wednesday at Maxim's 10th Annual Hot 100 bash in Santa Monica, Calif. "We wouldn't be together without Kristin, and she's one of my favorite people I've ever met."

The new season, Heidi said, will be "ten times better!"

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Cavallaris first appearance will be on the May 31 finale, where she catches the bouquet at Heidi and Spencer's wedding.

See personal photos from Heidi and Spencer's wedding

Spencer told Us that Cavallari will bring some edge to the show that Conrad didn't have.

"Lauren didn't date a guy for three years," he told Us. "Kristin's going to date three guys every day!"

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Said Spencer, "If Kristin Cavallari were to come to The Hills, I would stay on the Hills for twenty seasons!"

Spencer's sister Stephanie isn't so sure.

"I'm terrified!" she said. "She's no Lauren Conrad. And she loves drama and catfights. I saw her on Laguna Beach. I'm freaking out."

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But Audrina Patridge said bringing Cavallari on board is "great."

"It'll add a little bit of spice to The Hills," she said. "I don't really know her that well. I hung out with her a couple times, and she seems like a pretty cool girl."

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Still, it'll be different without Conrad.

"I'm so used to always talking with Lauren and filming with her all the time," she told Us. "I still talk to her off camera, but it's little weird not being able to film with her."

Tell Us: Who would you rather watch on The Hills - Lauren or Kristin?