Product review (5 stars): A Great Price
They arrived on time, I replaced my old cartridge with one of the Waterdrop LT6000 replacements.  It fit right in with a counterclockwise twist to install with no problems.  No leaks or anything.  So far there are no problems and I don't expect any.  Water tastes the same as before.  I just replace my filters every 6 months when the digital display illuminates.