Thanks to all for the input. The Timberline looks promising, definitely lighter at 5.6 oz. than all of the mainstream filters, and much better price. The Seychelle, of course is even lighter at just 3.6 oz. and just as inexpensive. Still, there seem to be no takers, or are there?

Thx Aaron for the links, most instructive. I can only recommend to all to read these articles. I was suspecting something of the sort. Rockwell, for example cites a study of a survey of the state health departments: "“Neither health department surveillance nor the medical literature supports the widely held perception that giardiasis is a significant risk to backpackers in the United States. In some respects, this situation resembles (the threat to beachgoers of a) shark attack: an extraordinarily rare event to which the public and press have seemingly devoted inappropriate attention.”

Given the scientific evidence that Rockwell and others present, it seems entirely reasonable to not treat spring water at all, as well as surface water at higher elevations. The lightweight solution thus might be to follow Rockwell's smart drinking rules, and then just carry a little Klearwater as backup should one be forced to drink from a suspect water source.

Edited by tgruene on 09/01/2006 14:58:38 MDT.