My boyfriend and I (20 and 21 years old), took what was my first cruise and his 3rd on the Costa Magica. Overall, the experience was wonderful! We booked through an online agency and got a great deal: $750 all together for an inside cabin, two people, including travel insurance!
EMBARKATION We used the parking service that is linked on Costa's website, and were very happy with the deal we got. It was $54 for the week, as opposed to $12 a day at the port. They also offered shuttle service right to the terminal, so it saved us the walk from the port parking garage.
We arrived at the terminal around noon. We left our luggage at the curb with the porters (Don't worry if you don't have your luggage tags yet, THEY HAVE THEM THERE!). It was a pain to stand in line, but what do you expect?! Sorry, but unless you're royalty you're going to stand in line like everyone else. It took about an hour and a half before we were on the boat, but it went off without a hitch and I was very satisfied.