I bought this water bottle for traveling - since I could roll it up in my carry-on, fill it with water and when finished roll it back. It is virtually weightless and easy to fill. The bottle holds 500ml which is enough to quench anyone's thirst.
The top is difficult to open without physically pulling on it, and the the water does heat up quickly inside the bag. I have noticed a funny taste after washing out the bottle, that seemed to go away.
Overall, if you are embarking on a trip, I would highly recommend this. If you are hoping to use it daily, I would suggest a SIGG bottle.