For $10, its not a bad price, each one is a different but cute design. They come empty but can be filled easily with or without a fiter. They are the same size as some of the sanitizers you can get from the Dollar Store, so if you wanted to, you could easily just buy some scented ones you love and put in them as well.
There is one small flaw, the unicorn designs can come off quite easily so they might not last very long. Should be able to re-glue it back on. I flung them around a lot for some testing and the bottle stayed inside the plasic very nicely, barely budged from it so it should be safe to attach to whatever you prefer. Purse, backpack, etc.