TeacherRO, hardly as scientific as the Overland Journal tests, but I really like the Katadyn Pocket, even more than MSR and Katadyn Hiker Pro filters I have used in the past. The Pocket retails for $250-275, but is an all metal construction, direct in-line pump action, and has the usual features (easy to clean etc) and has an enormous capacity compared to standard hiking filters (1 qt/min for 13,000 gallons). The Katadyn Expedition was even better, 1 gal/min for 26,000 gallons, but retails for about $1000-1200: definitely an expedition grade filter. In the field (hikes) people really like pumping with the Pocket compared to a Hiker Pro, which tends to feel a little cheap (all plastic) in construction, and its just plain easier to pump the Pocket. That said, most are happy with a Hiker Pro for their water needs, and why not, it only costs about $50 and a single filter tends to outlive the pumping mechanism.

I really like the Katadyn models, and the Pocket has all the tradeoffs I have made for personal water protection. If I had a bunch of people to pump for regularly though, I would consider a filter with a greater capacity, but right now I tend to pump for my own family or a bunch of Scouts.

Standard disclaimer: no interest in Katadyn or any vendor, just a happy owner and camper.