Best decided through the old fashioned retail experience. My advise would be to give a music shop a call and ask them to set up a demo for you then have a couple of need brandy's and see which copes with your rendition of 'She's a Lady' by Tom Jones best.
I have a sure BG1. I don't think you can get them now but they're a little cheaper then an SM58 and more suited to slightly lower frequencies. I originally bought it to cut through crowd noise when I was a DJ in pubs but it's still going strong. Just as with buying a set of speakers you can't make an informed decision until you've tried mics out for yourself.
This Is My Song
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I live in Lancashire, England.