IMO, unless it's a tribute act, then it's all down to artistic choices ... and as long as both the band and the audience enjoys it, isn't that what really matters? I used to play in an 80s covers band and we'd often spend weeks of rehearsals getting a song as close as we could to the original and the audience wouldn't really notice and then we'd play a punked up version of something like 'Walk Like an Egyptian' ... as far from the original as you could get (even had a male vocalist) and they'd be asking us to play it 2 or 3 times, they liked it that much.