While some 'Fifty Shades of Grey' fans continue to gnash their teeth over the casting of Charlie Hunnam as Christian Grey, the actor's 'Sons of Anarchy' co-stars think he'll be great -- even if one would rather not see his naughty bits.

"Charlie's the man for the job. He's really not afraid of taking on big challenges,” Maggie Siff, who plays Hunnam's wife on the FX series, told E News. “I really think he's going to step that movie up. It's going to be exciting."

Kurt Sutter, the series creator, added, "He's a movie star. We've known that for a while.”

But at least one co-star isn't so thrilled about the casting. Kim Coates (Tig on the show) says that although he's "really proud" of Charlie, he'd rather his friend keep his clothes on: “I don’t want to see him naked and everyone else does, so that’s fine!”

'Fifty Shades of Grey' is set to hit theaters next August.

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