To function:
The cup is tight, even if you shake him, dripping nothing out. The button for unlocking is super convenient - it works well when driving in passing. Previously I had a (just expensive, but not so long hot holding) stainless steel cup of Starbucks with such a stiff sliding bolt. As the button is already the better system.
The cup keeps drinks very long hot - almost too long. I have got used to the morning for twenty minutes to let my tea in the open beaker to cool slightly, then two hours later that he has the perfect drinking temperature. The problem was initially, the lid to close "appropriate". Once screwed tight and then he just goes very very hard on again. Those without strong man at home, perhaps then a problem ... But maybe also lags on me ... Meanwhile, I've got the hang of well ^^
I have a cup of the older generation, that is, the lid can not be broken down. No problem, just put in the dishwasher so, done. Supposedly not the thing Dishwasher be (according to the manufacturer), but for me it works wonderfully. The detergent discolored the cup in some places a little grayish, is for me but not a major shortcoming. In some reviews is talk of peeling paint. The joined me at the bottom, after 4 years of continuous use. Since the cup has now not even a 1mm wide edge without coating. Could also be tuned that I do not sink the thing manually. Or that it from time to time mitfährt on my car roof ;-)
Conclusion: The cup is really worth every euro. As it stands, holding the probably another five years, but maybe I'm considering some games, the new model with the folding lid. Who is deterred about the price, just believe me: this cheap plastic waste (Starbucks, Tchibo, I already have everything by) is a waste of money (does not keep warm), especially: will you still taste tea / coffee and no plastic, right? This cup keeps its promises, and you have what it long. Strong buy recommendation!