While I love the concept of double-wall, the problem appears to be with the thinness of the glass. While drinking a bloody mary, I ended up almost drinking the glass that broke in the first layer of the glass. I was very reluctant to let others use these products because of this flaw. The double-wall does do its job and resist condensation; however, overall I am very disappointed with the product. I would prefer to spend more and get a better product.