I bought 15 of them from Halloween Asylum a couple of years ago. Beats messing around with stacks of PVC and pool noodles and rolls of chicken wire and bubble wrap. I think it's important when you're trying to do something on the cheap that you consider how much it will cost just to buy what you want to begin with.
Plus, as you said, they don't take up any storage space!
Plus, as you said, they don't take up any storage space!