I drink both, but I prefer flavoured. The one I drink mainly is strawberry and kiwi. I used to drink mango and passionfruit too, but the supermarket stopped doing it in anything but sparkly.
Love very cold water, or Sparking Mineral Water.
Sometimes put Cordial in it.
Always carry frozen bottle Water when shopping.
I like bottled Spring Water, for its' taste.
Drink gallons, as sweat, even in Winter!