Bests & Worsts Reviews from Amazon

I purchased this to produce a spotless rinse while cleaning cars but ran some tests on the filter. Long story short, it didn't work out. Here's how I tested: After receiving the filter, I attached to my water spigot and purged for 2 minutes. I took glass 1, rinsed and filled the glass with filtered water. I removed the filter again and filled glass 2 with tap water. Examined 3 areas: 1) VISUAL: Both tap water and filtered water appeared clear or colors or sediment. PASS 2) TASTE: The filtered water had slightly less taste, but hardly noticeable: BARELY PASS 3) TDS metering: I bought a "Total Dissolved Solids" meter than measures purity. (ex. tap water: 100-400ppm - Distilled water: 0ppm). My tap water measured at 402 ppm, but the filtered water came in at 442ppm!! What?? The filtered water came in LESS pure? Most likely the higher TDS rating likely came from harmless excess sediment from the carbon filter. It appears these carbon filters are designed to only filter out non TDS solids (ex converting gross well/hose water into more pleasant drinking water). OVERALL: These may still be good for converting clean hose water into something more palatable for RVs, but certainly not for creating a spot-free rinse. I don’t think any carbon filter can obtain a low TDS (spot-free) rinse. If that’s what you’re looking for, your remaining options are likely either triple osmosis or distilled.