Ross is right. If you are going to keep them longer though you aught to give them a small drop of honey every other day and a drop of water the other days.
I got 200 queens in the mail almost a month ago. One hundred were for a friend of mine.
The last two queens went to another friend yesterday. I kept them going w/ a drop of water one day and a drop of honey the next. When the attendants died I removed them, which can be tricky, and replaced them w/ new worker bees. I didn't loose any queens.
I wouldn't bother banking queens just for a couple of days.
"It's not what you look at that matters, it's what you see." Henry David Thoreau, Mark B