I Bought two tickets for Iron Maiden off ebay last year .
and Two for Bruce Springsteen (can't stand him but it was the wife birthday prezzie 4 hours of lift music
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)
Met the guy in a pub in Manchester had a pint then went to the doors where he handed in the tickets we went in then I paid him perfect. I think as with anything if you check feedback and do your checks you should be ok.
The gig was good to Trivium supporting 8)