Instruct: Classify Amazon reviews into positive or negative sentiment
Query: great looking, more durable than they look, don't stack well

These glasses look great and the double wall design keeps beverages at temperature without hot drinks burning your hands or cold drinks sweating and ruining tables. The glass is very thin and they look like they would shatter at the slightest touch. Because they are made of borosilicate glass they are much more durable than they look. Using borosilicate allows them to be extremely light but reasonably durable. Because of their flared shape they don't stack very well. They fit inside each other just enough to be stable but stack best inside the largerLuigi Bormioli Duo 16-Ounce Beverage Glasses, Set of 4