1. 6 months
2. Probably once a day on average (although some work days I CBF cooking AT ALL so I wouldn't use it then). And more often now that I'm getting into breakfast smoothies.
3. Peanut butter, chickpea cookies, breakfast smoothy, pineapple whip, banana muffins
4. Any cake/biscuit batter, risotto (I never cooked it before getting the thermi), sorbet or the like (a great, easy one is frozen banana whipped up with peanut butter. It's sooooo yummy & ice-creamy but EASY and good for you too!)