For a real party Highly Recommended

Freezing works without problems.
Of course, the ice melts, ie it must be drunk relatively quickly. To enjoy such as Ramazotti the glasses are not suitable. To pour a round at the bar, so that everyone has something, but time enough. After drinking just throw in the sink.
12 glasses are a little bit, so preferably before the Party freeze several passages, detach and store separately in a bowl (or similar) in the freezer.
Leaching is not easy. Best own technique to find out. I always am running a little warm water on the back of the form.

Conclusion:
Those who do not work, this product should not buy. In addition, the glasses are in my opinion not suitable for a cozy get-together.
For a real party, the work but worth absolutely that glasses bring a lot of fun.