In short: The locking mechanism is all top notch. You press the big button and spout and vent open. One lets go, and everything is sealed. Lately has the button even a locking feature that gg. Unintentional operation protect. Everything was perfect with a hand operated blind, which is very convenient, especially in the car!
The stainless steel body fits perfectly into all standard drink holders. Both parts are dishwasher safe, although some flyers saying something else (but that refers to the Kunsstoff-butts!).
The only drawback: The locking mechanism is completely inside of the cup, and thus comes into contact with the contents. This is usually not a problem, BUT:
If you have forgotten eg coffee with milk on / two days in Contigo since formed easily mildew!
That's probably for all those cups of case, but here always some mold stuck somewhere. Why did my first with just about everything maltreated what a chemist can think of ... Hot Domestos, bathroom cleaners, alcohol, bleach - everything what you must give in no case in the cup according to the instructions! The cup has it endured, the mold unfortunately. At least this was grumpy odor not want to leave, as I have thrown away the cup.
At Contigo Europe you can indeed order replacement parts, including whole cover - but that would have paid off with Porto from Belgium only as a collective order.
So - brilliant cup, always rinse well, then you have a long pleasure! :)