I love this idea!!
I've forgotten about the unpleasant feeling of opening the bottle and getting a weird canteen smell with the simple gesture of pressing a button. I keep the bottle in the office and it is always in fresh, clean water.
The battery lasts for many uses and charges quickly.
For me the size is perfect, I can carry it in my bag, it is comfortable.
The but...at first I had a hard time understanding the security system on the cap, which is great, but you have to make sure to close the bottle with the cap properly for the system to work. Once I figured it out, it was great, no problems.