Reverse Osmosis wastes an amazing amout of water. Something like 2 gallons of water goes back in the sewage system for every gallon that you get out of the RO system.
Read the label on bottled water. Some bottled water is filtered, some comes right out of the same water system that feeds your house.
I personally use a Brita filter for drinking water at home because I prefer the taste and if I buy bottled water I buy water that is either filtered or distilled.
And if you are really worried about the water quality coming out of your faucet, you should get a filter for your shower or a whole house filter. Your skin will absorb all the bad things in the water when you take a hot shower.