I usually try to get Penta water cuz it tastes sooooo good! But they are also bottled in plastic. Their website insists that their #1 plastic bottle is much safer than the flimsy Aquafina-type plastic bottles, and it IS much harder. But I don't know enough (anything, really) about plastic to know if this is significant.
I have been trying to phase plastic containers gradually out of my home; buying glass storage containers when they're on sale. I never put anything hot into plastic and although I don't use a microwave I try to encourage my husband to at least use glass when he does. I think I'm wearing him down on the microwave issure though; he's using the toaster oven more and more...but that's a whole new can of worms!
The best I can do with water for now is use a refrigerator pitcher at home for financial reasons. Since I have well water there is no issue with fluoride or chlorine, but the city is trying to impose on me and get me to use their poison water with some legal battle...