I'm looking to buy a reverse osmosis water filter. Before I buy one I would like to know some of your opions on a good brand to buy. Any feedback would be much appreciated.
I suggest you be careful about the ebay route, unless you are very clear of what you want. There are all sorts of very odd configurations on systems on ebay - everything from horizontal DI cartridges, to carbon after the DI, to parts with no specifications, etc, etc.
Can you get it very cheap on ebay? You bet. Just beware of what it is you are, and are not, getting.