I've had my cup for about a week now and am filling it up religiously. Ok well maybe not that much but I am making sure that I'm drinking more water. After the first day, my boyfriend asked "whats up with you and the water?" I used to drink bottled water but I think he asked because I was walking around the house with ice clinking in it and it was distracting. I think a big factor making me want to drink out of it is the straw. I can't explain it but I've noticed if I'm given a drink with a straw in it, i'll end up drinking the whole thing. But if I'm at a restaurant where they don't give you straws, I drink less.