Hi, Both are acceptable, although #2 seems a little more correct if you think about it for a while. To some extent, I'd say it depends on the band name. eg You can say 'Mick Jagger is a Rolling Stone' or 'Ringo Starr is a Beatle', but it doesn't sound quite so right to say 'Angus Young is an AC/DC'.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.