It's amazing what some people will pay for water. I work for a beer distributor, we also have some high-end waters. Both Icelandic Glacial and Mountain Valley Spring Water go for about $20 for a 24 pack of .5 ltr pet. It sells, even in an area where sanitized and filtered Lake Michigan (fresh) water is the primary source. I just don't get it...I heart my tap water.
The bottled water here is very high acid, which I discovered when my wine (mango) was so high. I tested the water and BAM there was the problem. Turns out, it's the acid they use to recycle the large 5 gallon bottles. Of course I am in a 3rd world country. I treasure the filtered rainwater - not a problem ever since!
It is great - my first batch was small (1 gallon) but fab and when I tried to duplicate it the only variable was the water (we had moved from a house with a cistern to a well, thus I had to use the bottled water). My other attempts were a disaster. Mango season is only May - Oct and it was dry so we are just now seeing out first good mangos and we have a cistern again. I have 3 batches (at least partial mango - mixing with bananas and pineapple) going and more to follow. Will let you know the outcome