I don't believe you can buy the soda package ahead of time - I think you can only get it on the ship. It is not a card but a sticker that they put on your seapass. You also receive a CocaCola travel glass with the purchase. The cost is $6/day for adults and $4/day for children plus 15% tip and tax (if you buy it before you sail). I have never gotten it before but I did get it on the Voyager in February and I did like having it. I drank a lot more soda and less water, lemonade and alcohol because I had the card. I don't know if it saved me any money but I enjoyed getting a soft drink whenever I felt like it without worrying about how much I was spending. This is currently the only type of drink program that they have now that they have eliminated the alcohol drink card program. I hope this helps!