Product review (1 stars): 200 ppm with old filter, 300 ppm after installing this one.
Replaced the filter using one of these Blue Mountain BM-LP8 filters.
Our sink water tested at 400 ppm and our old filter tested at 200 ppm, so I thought changing it was necessary.
The Blue Mountain filter (even after running the suggested 4+ gallons through it) tested at 300 ppm.
The only difference between the filtered and sink water is the smell is better and a slight difference in ppm.  100 ppm is not a big difference considering that filtered water should be <10 as far as I have seen on youtube vids.