Do bottled water companies use reverse osmosis filters?

Do the major companies like ozarka, crystal springs, arrowhead use reverse osmosis filters?

Just wondering what's better to drink at this point -- bottled water or tap water. We're renting so I can't really add a whole house filter right now.

My understanding is that

My understanding is that Dasani is RO tapwater with some minerals added (not many).

I think springwater is springwater, no filtering, so quality depends on the "spring." Some "springs" are more like completely underground wells, and I would think some well water is better than anything that got surface contamination in it over the last few months.

Not that it's a guarantee...

....but a lot of the companies put on the label whether or not they use reverse osmosis, i.e. Kirkland brand (for Costco) has it written up the seam on the label. You can either check or call the 800 number on the bottle and ask. A lot of water stores also use reverse osmosis. It doesn't hurt to hit up the local store and ask. We recently switched to a particular water store because the lady who owns it not only charges a good price (.25 a gallon instead of 2.99 for a 2 1/2 gallon jug from Bel Air) and she actually took me back into the back of the store to see her system and how it works.