The folks at NPR wondered if $55 Bling H2O really tasted better than other bottled waters. They conducted a taste test featuring Bling H2O, normally-priced bottled water, and Manhattan tap water, and posted a video report. I don’t think the results will really surprise you. Link -via Metafilter
http://youtube.com/watch?v=XfPAjUvvnIc
My wife & I spent $150 on a reverse-osmosis system back in the early '90's, have kept it up with fresh filters, and our water tastes far better than anything you we've tasted from $1.50 bottles. I think the total cost for water from our system, including filter changes, is under 10 cents a gallon.
Well worth the time and effort, even for apartment dwellers.