This talks about it.
http://www.rei.com/product/767831/first-need-xl-water-purifier

The information:
Structured Matrix 3-stage purification technology provides natural and ecological removal of contaminants down to 0.1 micron nominal (0.4 absolute)
Purifier is certified to EPA Guide Standard for microbiological purifiers against bacteria, cysts and viruses; removes giardia and cryptosporidia
Also removes dirt, unpleasant tastes and chemicals such as pesticides and herbicides
Easy-grip, ergonomic handle provides comfortable pumping; double-action pump is field serviceable
Use the included gravity feed kit for hands-free purification without pumping
Fast flow rate of 1.89 liters per min. lets you enjoy clean, great-tasting water in no time at all
XL purifier's large capacity lets you purify up to 150 gal. before needing to replace the canister
Direct Connect attaches unit snugly to many wide-mouth and narrow-mouth water bottles and hydration systems, sold separately
Attach the drink tube on your Camelbak® hydration reservoir directly to canister so you can refill without removing the reservoir from your bag
Additional adapters (sold separately) allow attachment to directly to select Platypus, Sigg and Nalgene water bottles and reservoirs, sold separately
Included prefilter removes larger contaminants before they reach the purifier; adjustable float lets you position the prefilter exactly where you want it
36 in. long inlet hose provides consistent flow and won't kink
Excellent impact resistance withstands use in the wilderness and during international travel
First Need XL water purifer includes a lightweight storage bag
16 oz. weight includes filter canister (does not include storage bag)

Made in USA.

aprox 13 M households get water from private wells

That looks good. I would get it. I've been eyeing the kataydyn hiker pro

a bit more in my price range

surface waters are difficult to guard

this is crazy:

I am concerned about the municipal water system becoming contaminated because of some sort of disaster. My thinking is (as we had a few years ago with the flooding associated with our 24 inches of rain in a couple days) there may be human waste, dead (animal) bodies and etc contaminating the water available (ditches and ponds, etc) after the failure of the municipal water supply.
We live in a rural area and our town is only about 1300 people.

in 1990 197 M pounds of toxic compounds were INTENTIONALLY released into US waterways

I just don't completely trust the "Survival straws"

Yea that is scary. What do you do then, ya know?

I've seen the first need for less than $90.00. For safe water that doesn't seem to bad to me.

PUR has some products out that do larger amounts of water. They have kits that come with 2 foldable jugs and flocculation packets and chlorine tabs