Maybe not Private Eye and NME then, maybe Goth Weekly or whatever. Or whoever published the review in the first place. Try to get them to print an apology: "We may have given the impression that going to this gig was a waste of time, and buying their new record is inadvisable. We apologise for this assessment - on reflection we realise that going to any gig by this band is a waste of time, and that if you have bought their record you should return it immediately under the Trades Descriptions Act for calling the band 'artists' instead of 'talentless sacks of shite'". Or words to that effect.

I reckon that whatever the size of the band, there's bound to be a magazine which is small enough to give a toss, but also large enough that the band can't threaten them without defaming themselves far more than the original review could possibly have done. And no magazine is going to take kindly to a band which threatens to sue a reviewer, so it's worth offering them the opportunity to take the piss.