"Problem resolved"
I bought this water bottle some time ago, and like other reviewers had the same problem trying to suck the water out. I was on the verge of returning, until I stumbled across the solution to the problem which I hope, by sharing might help others. To make the bottle work properly you need to make sure you fully open the mouthpiece as far back as it goes. It then works brilliantly. Since my discovery I have been really very happy with the bottle. It's been great.