Even worse than copy-cat covers are people who make blanket judgements and who like to tell other people what music they should play and how they should play it. I'll listen to a well-played cover any day if it means I never again have to listen to someone tell me - or anyone else - that we're playing the wrong music or playing it in the wrong way. Or have to listen to someone say, "If you can't do such-and-such you shouldn't call yourself a musician."