The 'Eez-eh' hitmakers will be headlining the Glastonbury festival alongside Arcade Fire and the legendary heavy metal band next week and they think the group are a ''controversial'' booking.
Serge said: ''Metallica, they're massive. I'm being entirely honest with you, I don't really know their tunes but they're massive.
''They've been doing it for a long time, so they'll have a few tricks up their sleeves. It's been quite a controversial choice but I think that can also work in your favour. I've met Lars [Ulrich], the drummer. He came to a show of ours in San Francisco and was a lovely chap, so I wish him all the best.''
However, the band - also made up of Tom Meighan, Chris Edwards and Ian Matthews - have been checking out Arcade Fire and are a fan of their album 'Reflektor'.
Serge told NME magazine: ''I've only seen little bits of pictures and stuff but they seem like their live show is interesting. They seem like a great band for a Friday night.''
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Roberts had left the band in 2012, due to problems with blood circulation and other health issues.
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