Touring water system filters

Whats a good bicycle camping water cleaning system folks use?

How do folks remove viruses from filtered water?

Listed below is the MSR MiniWorks and MSR HyperFlow.
The little bit I know I'm leaning toward the MSR MiniWorks.
I will be using it in streams above rural towns.
Thank you for your thoughts, suggestions and help.
-Mark Hoagy

http://cascadedesigns.com/MSR

MSR MiniWorks EX - $89.95
Better-tasting Water: Carbon core removes unpleasant tastes and odors
caused by organic compounds, such as iodine, chlorine, and pesticides.
Effective against protozoa	Yes
Effective against bacteria	Yes
Effective against viruses	No
Effective against particulate	Yes
Effective against chemicals/toxins	Yes
Weight	1 lb / 456 g
Width	2.75 in / 7 cm
Length	7.5 in / 19 cm
Filter media	Ceramic Plus Carbon
Filter pore size	0.2 microns
Flow (L/min)	1 liters per min
Flow (strokes per liter)	85
Cartridge life	~2000 liters
Field cleanable	Yes
Field maintainable	Yes
Country of Origin	Made in Seattle, USA
Mechanical advantage	Yes
Water Bottle Adapter	Yes
Cartridge replacement indicator	Yes


HyperFlow Microfilter - $99.95
Ultralight: Just 7.4 oz. (209 g).
Ultra-small: Just 7x3.5 in. ( 17.8 x 8.3 cm)
Effective against protozoa	Yes
Effective against bacteria	Yes
Effective against viruses	No
Effective against particulate	Yes
Effective against chemicals/toxins	No
Weight	7.8 oz / 221 g
Width	3.5 in / 8.3 cm
Length	7 in / 17.8 cm
Filter media	Hollow Fiber
Filter pore size	0.2 microns
Flow (L/min)	3 liters per min
Flow (strokes per liter)	20
Cartridge life	~1000 liters
Field cleanable	Yes
Field maintainable	Yes
Country of Origin	Made in Seattle, USA
Mechanical advantage	No
Water Bottle Adapter	Yes
Cartridge replacement indicator	No