Thanks for your input! I do have a couple of follow up questions:

1) You mention drinking bottled water first. What are your expectations of the water quality from the product? For example, strictly filtered water might be perfectly healthy, but cloudy or have smell/taste. Distilled water would be as pure as (if not more pure that) bottled "mineral water". What is acceptable? Would you pay more for a unit that made "better" water?

2) How important are asthetics? Would a unit that looked like a scientific instrument be more or less desirable than something slick and consumer oriented? (Think Brita filters ... clean lines, plastic case, blue and white, etc.)

3) How important is portability and how do you define it? Small but heavy would be easy to store, but may be difficult to carry around. Something that one person could lift, but was too big for a car trunk (you need a pick-up) is still technically "portable" but may not meet your needs.

4) Product life has many definitions. A product could make unlimited gallons, but not be re-uasable in the sense that once stored for some time would no longer purify effectively. (After a disaster, it would meet unlimited need, but you would need to replace it once utilities were restored.) Another design might be usable over and over again, but durability is limited to, say, a hundred gallons over it's life. (It would survive mutiple disasters, but you would need to be aware of how much you used it, and plan accordingly.) What do you feel is the more desirable goal?