What everyone else said.
I just wanted to add that I am so bummed out that I didn't buy a half-hour glass that Adam's grocery story (here in New England) had on offer last fall for under $10.00! It was a beautiful one, and if the offer ever comes back, I'm buying it!
I think about it (lustingly) all the time.
So, do yourself a favor. If you see one at a good price, buy it.