Product review (4 stars): Replaced 3 year old filter
The water company performed work on the water main in the street causing brown water to flow in my house for hours.  Apparently this clogged the filter because the flow rate was greatly reduced out of the tap.  After installing a new filter the flow was back to normal.  The new filter installed easily, didn't leak, and performed well.  I cannot say if it actually filters anything meaningful (chlorine, bacteria, etc), as I do not have the willingness or ability to test, but I can say it certainly does filter particulate as evident by clear water coming out of the tap while all my faucets produced a brown soup.

I cut the old filter in half to see how it works and will try to post an image of the cross section.  The filter has no moving parts.  It is simply a cylindrical carbon based (I assume) tube that passes water from the outer surface through to the center.  In the future I'd like to try an off-brand filter and see how it compares functionally and internally but at 40 bucks every 3 years, I can swing I new GE version.  (I know GE wants you to replace it much more often but I refuse to believe that is necessary.)

I'd give it 5 stars if I new exactly what it was and wasn't able to filter AND if it where about 20 bucks cheaper.