Well, boiling water has its place, Fred. But really, after being out longer than a day you're more than ahead of the game by carrying a filter, rather than lugging the fuel you need to boil three or four quarts a day.
As far as the Katadyn Pocket water filter goes, it's certainly a nice unit. Very ruggedly made of steel and other tough materials; it's a lifetime investment. But it's slightly heavy at 1 pounds 4 ounces. And expensive? At $320, yes.
These days the only other real game in town, aside from standalone bottles with a built-in filter, is MSR. Their newest offering is the HyperFlow ($100), which is a unit that attaches to a wide-mouth bottle via a proprietary assembly, and the bottle in effect becomes the pump body. It's light (8 ounces), and pumps a lot of water fast—not too far from three quarts a minute. I will say it has not been wildly well-reviewed by users, many of whom complain about its delicacy and tendency to clog. Some users love it.
To me, a more proven technology is the MSR MiniWorks EX ($90), which has been around for well over a decade. It's the filter I use, and it's sturdy, easy to use, and has good output. Easy to maintain, as well.
For one person, a good solution might be Katadyn's MyBottle filter ($50). It's a complete bottle/filter assembly – just fill it and drink.