The insulating effect is negligible compared to cups or glasses more. Most of the temperature emitted just upward therefore the tea For example for stays not really warm longer than in a cup.
The glasses take on very stable and also make a stable impression. They can also be cleaned in the dishwasher without any problem. The equalization valve allows only air through and no water.
The glass ansich has no impurities or irregularities. The glasses are all different heights (deviation about 2-4 mm). I guess that comes with the manual production.
But now the biggest minus point: the surface. Despite elaborate packaging had 5 of 8 glasses small scratches of about 1-5mm. For the price and this exclusive product category is absolutely incomprehensible. I keep them in spite of conversion and renewed scratch after a long weighing up anyway.
The double-walled tea glasses of Tea Forté, in comparison to no scratches and can be had for the same price.
