I also own one of the cups and it took me About 1 year figuring out how to drink, so that it does not drip. It is simply in front of a design flaw, so that excess liquid flows back into the lid and then later emerges between the lid and cup. So to avoid this, one must after every sip, which one accepts, sipping tea / coffee from the lid. This is a bit cumbersome, noisy and you wear them in a quiet lecture often to general amusement at, but you have not run around the rest of the day with a bekleckerten shell then. So again: It may at weaning of the cup no liquid in the lid will remain (exactly between "Mouth attachment point" and EMSA logo), otherwise it later drips. I hope I could help some frustrated people!
I personally would not buy me the cup with this locking system again, even though he keeps drinks hot and long, the size is very good.
