We got the soda stickers (yes, there were two of us, and we are too honest to "share!") on the Grand Princess. It IS a great deal if you drink a lot of soda. We asked for a "large diet Coke" and we got something near 20 oz, so it lasted a while. However, unlike Celebrity or RCI, I noticed that once a cocktail waiter got you a "free" soda, they would do big circles around you to avoid having to do so again! Never a problem at the bar, but the waiters stiffed us. Nevertheless, it's worth the cash if you drink more than 3 a day.
Lemonade was not available. I asked the server the first day what was a free drink and she said tap water, tea, and coffee. I found out about the milk and juice later on my own (maybe servers are not willing or allowed to serve them to you during the day?). I also asked the bartender if I can have a sprite and lemonade mix and his reply was I can add lemons to your sprite. I took that as no lemonade (at least in the bars). However I did not see leamonade during the 10 days on board.