Do you have to let all juices steep, or is it just the one's that are mixed on-site? I bought some from a local B&M store, and they had great taste. Tried some at another, liked it, bought some that they mixed up right there. Once I got home I tried it, but didn't have the flavor of the sample I tried. I'm guessing I need to let it steep. And how long should I let it steep? Thanks in advance!