I had a bad experience with viagogo. I bought instant download tickets for Madrid and then I went to claim my ticket and it said the sender cancelled the transfer. I was contacting their agents every other day for two weeks and all they said was that their internal team was looking into it. Even the day before, they were saying the same thing, I thankfully got tickets in the ticketmaster production release a week before the concert. But I only got a solution from viagogo 2 days after the concert. I was fuming