So - you go online and buy a ticket. Guess what happens when you show up? They say "that's just a voucher, now you get in the ticket line, like everyone else, and they give you a ticket"
So we had showed up early, and it was crowded. We bought tickets online to avoid that. But we had to wait in the same line as everyone who just showed up - the TICKET LINE - for 45 minutes, to get our tickets.
We had read it was "first come first serve" as to getting on the ship. So our wait lost us any good seats.
Do not use this - show up early and buy the tickets in person.