Review on Pentek FloPlus 10BB Activated Carbon Filter Cartridge by Jane Cuperus

Bought a new house for us about 4 years ago and found the house didn't have a safety valve or filtration system and I'm not a fan of unfiltered street pressurized water so I'm saying it in a PRV with one 4x20 filter housing. First I put a regular filter in, I think 30 microns, and in 3 years we haven't had a huge pressure drop. Realizing it doesn't filter anything, I did a little research and finally bought this filter (FloPlus-20BB). I like him. Flow is great even with two running showers and laundry but that's only enough for about 3 months with a family of 5. I have had virtually no pressure drop for 2 months, but by the end of the 3rd month it drops from 55psi to 25psi when we're working wide open. My system has 3 gauges, street, pre-filter, post-filter so I can tell when I need a replacement fairly quickly. As others have pointed out, all of the chemical taste in our water is gone. In our case, the filter clogs long before the carbon stops working, so in my future the pre-filter might be $75 a filter. Every time I need to buy a replacement I look at them again and I haven't found anything cheaper that gives the same good result. Open to suggestions!