I always get the soda card, but gdjoslin is right, unless you drink alot of soda it might be better to just buy what you want. I am a Diet Coke drinker and I get a soda at the pool, watching the shows, at a bar, dancing, waiting for friends....I make sure that I use it often
Note to ToddinCanada - I have not had a sticker put on my sign and sail card, always have had a seperate card! That would be MUCH easier!
PS I don't buy the card on the first day because too much running around - I get it the second day - and yes, they prorate it so it is cheaper each day