Product review (4 stars): Stick With the Genuine Filter
Due to the high cost of these Whirlpool approved filters, I tried a cheaper generic-brand filter last time and tasted an immediate drop in the taste quality of the water. The funky-tasting water left me regretting cheaping out for the last 6 months.  Now I've switched back to these genuine filters and the water tastes immediately better.  I still don't like the high price (hence the 4 star rating), but in the 2 pack the price per unit is more bearable.  Its just not worth having crappy-tasting water to save a few bucks with a generic filter.