At some point, everybody dreams of being a famous musician, touring around the world and performing for screaming crowds. Everyone can also relate to the movie star dream, imagining moving to Hollywood, making hugely successful movies and walking red carpets looking glamorous. Recently, Kristen Stewart and Dakota Fanning premiered their upcoming rock biopic "The Runaways" at Sundance, enjoying the best of both fantasies before either one has turned 20.

So, from folks who are neither to women who are both, we had to ask: Which is more awesome, being a rock star or a Hollywood star?

"Hmmm," pondered [article id="1630370"]Stewart[/article], who, thanks to the "Twilight" films, is arguably hotter than any actress in Hollywood at the moment. "What's cooler?"

"I enjoy being an actor pretending to be a rock and roll star," Fanning laughed.

"It's like the best of both worlds," KStew agreed.

The same could probably be said of these two actresses. These days, they've made back-to-back films (Fanning joined the "Twilight" saga for "New Moon" as the Volturi vampire Jane) and are so close in age and friendship that it seems like they could keep making movies together forever.

Previously, however, their careers were quite different: Stewart was known as an actress of great promise who already seemed grown-up beyond her years, while Fanning spent a half-decade as the ultimate adorable moppet in films like "The Cat in the Hat," "Dreamer" and "The Secret Life of Bees."

Now they've rocked Sundance as the Runaways. And what do their hands-on parents think of seeing them as hard-partying, drug-abusing punks?

"My mom has seen it," Fanning said a bit sheepishly.

"Nobody's really seen it for me," Stewart replied. "I don't know yet."

They will soon enough. Co-starring Scout Taylor-Compton, Alia Shawkat and Michael Shannon, "The Runaways" will open in theaters March 19.

The MTV Movies team is all over the 2010 Sundance Film Festival. Go to Sundance.MTV.com for exclusive clips, reviews, photos and interviews with everyone from Kristen Stewart and Ryan Reynolds to Ben Affleck and James Franco.

Check out everything we've got on "The Runaways."

For young Hollywood news, fashion and "Twilight" updates around the clock, visit HollywoodCrush.MTV.com.