I purchased 2 tickets for the concert of Madonna in Miami in Nov 19th 2012. She didn't appear until 4 hours later and I left before the concert started as many people did.
Those guys that bought through Ticketmaster were reimbursed in full but I bought my tickets from GoTickets.com and they didn't want to reimburse.
This is not good at all for a company that you trust in and that doesn't fulfill the same promise that their provider (Ticketmaster). I don't recommend you to buy tickets from them because you most probably will lose your money.