TBone, The system I've had the best luck with for long lasting function and no extra maintenance is the enviropure. It is mor expensive up front but comes with a 10 yr replacement warranty for any failures. It is available through www.enviro-pure.com. then click the contact us link. A guy named Daniel Brandon runs the show over there and he's good. He may give you a discount if you let him know Josh (Plumbtruth) told you to go there.
For more plumbing info I have a site: firstname.lastname@example.org you can check out.