These are hands down the best double wall glasses on the market. I have tried other brands only to have them leak between the layers, get cloudy in the dishwasher or break easily.
Hot beverages stay hot and cold beverages stay cold without forming a sweat on the outside of the glass. I can go to bed with an ice water and wake up in the morning with ice still in the glass!
I use these glasses every day, put them in the dishwasher and they look just as great as when I bought them 3 years ago.