Product review (3 stars): Forced Requirement
If you really think you need a filter, it probably works ok, but very expensive.  If you replace it every six months as recommended, it cost more than the electricity to run the refrigerator!  I couldn't tell any difference and replaced it after 2 years.  Unfortunately the water system is designed to NOT WORK if the filter is removed.  After a lot of digging I found a substitue bypass filter made by the same company. The part number is 740572 - same cartridge without the insides.  It cost a little more than with the filter, but at least you don't have to worry about bacteria building up in the filter and always paying replacement costs.