Product review (5 stars): Perfect fit, great filter!
I don't change the filter as often as recommended.  But when I do, I turn to this one.  I let it go for just about 8 months one time and can tell the difference as soon as it is swapped out - the water flows much faster and tastes much better.  I have found 5 months to be the sweet spot on the life of the filter for our family of 2.  We filter 4-6 glasses of water each day.  Obviously if you are filling large pitchers and have a larger family, you will need to use your best judgment.