A. O. Smith RO with Microbial Boost AO-US-RO-MB-4000 vs Express Water RO5DX
Only the A. O. Smith RO with Microbial Boost AO-US-RO-MB-4000 is certified to reduce PFAS, lead, chlorine and chloramine and 7 more. Verdict: the A. O. Smith RO with Microbial Boost AO-US-RO-MB-4000 for broader certified protection (12 vs 1 of the contaminants we track).
| A. O. Smith RO with Microbial Boost AO-US-RO-MB-4000 | Express Water RO5DX | |
|---|---|---|
| Type | Under-sink reverse osmosis | Under-sink reverse osmosis |
| Price | — | $190 |
| Filters + water a year (2 people) | $270 | — |
| Filter cost per gallon (rated life) | 37¢ | — |
| Gallons per day | 11.64 | 50 |
| Pure to drain | — | 0.33:1 |
| Installation | diy | diy |
| PFAS | Certified | — |
| Lead | Certified | Brand test only |
| Chlorine | Certified | Brand test only |
| Chloramine | Certified | — |
| Fluoride | Certified | Brand test only |
| Arsenic | Certified | Brand test only |
| Nitrate | — | Brand test only |
| Chromium 6 | Certified | — |
| Mercury | Certified | — |
| Cysts | Certified | — |
| VOCs | Certified | — |
| TDS | Certified | Certified |
| Copper | Certified | — |