We used them for a trip last year without any issues. Planning to use them again now for a trip at the end of July that we just decided to book. Now have to wait for them to get more of the 2 day tickets available.
They send you the paper tickets by mail. Came via 2 day FedEx. You can take them and go right into the park. BTW, the US tix did not require a team/player name to purchase.