This is an excellent bottle. I feel very comfortable having my kids use them. The only thing I do not particularly care for, is the rubber straw at the top. My youngest (4) seems to keep chewing on it and I'm afraid she may choke on it if it comes off. Other than that, my oldest commented on how fresh her water tasted (7, didn't know it was supposed to make it taste great) :) Sigg is a great company and I trust their durability and transparency in creating healthful products that last a very long time.
We started out liking these bottles, but within about a month the straw for one of them stopped working, despite the lid being in the Open position. I probably need to see if I can order a new lid, but it's a hassle. I am not sure why it seems to be so hard to find a water bottle that will last.
Just recently purchased 2 of these and both water spouts developed mold/mildew in the inside of the mouth piece within 1 month. Tried to clean with baking soda and vinegar as directed but still didn't get the spout clean. The directions say to wash and dry daily but find this unrealistic as my kids drink water 24/7.