I bought tickets for my family of four and for another family of 5 from Ticketmania. I ordered the 5 day PHs, which came less than a week later. They were paper tickets and were the same ones sold at the parks. We had no problems whatsoever, and I was happy of course about the savings.
This year, however, I'm going to get our tickets from TDS advance price, which is the lowest price I've found so far.
But Ticketmania is indeed reputable! Good luck with your decision!