I bought one of these yesterday and for the life of me, I can't get the darn lid off! Neither can DH. I am so frickin annoyed. Is there a trick I'm missing or something? It's the Playtex Insulator Twist n Click with Straw:
I got it off. I think it had developed a suction or something. Once I tapped it on the edge of the counter it came off with POP like a pickle jar. Hope it's not always that tough!