AQUASURE Premier Series 75 GPD Under Sink Reverse Osmosis Water Filtration System vs Watts 4-Stage Reverse Osmosis System 7100103: which is safer?

AQUASURE Premier Series 75 GPD Under Sink Reverse Osmosis Water Filtration System edges it on pure PFAS risk, but Watts 4-Stage Reverse Osmosis System 7100103 wins overall once other hazards are counted.

Aqua Guard

AQUASURE Premier Series 75 GPD Under Sink Reverse Osmosis Water Filtration System

PFAS grade

A 100/100

Overall grade

C 78/100

Verdict

Buy

Hazard flags

⚑ 4

Material

RO membrane, carbon filters, stainless steel housing

Confidence

72%

PossibleBacterial and microbial growth in housing and filters

PossibleActivated carbon filter degradation and dust release

ReportedRO membrane integrity failure and microbial breakthrough

Why this gradeBuy

Our pick

Watts Water Technologies

Watts 4-Stage Reverse Osmosis System 7100103

PFAS grade

A 95/100

Overall grade

C 79/100

Verdict

Buy

Hazard flags

⚑ 4

Material

RO membrane, carbon filters, polyethylene tubing

Confidence

72%

PossibleBacterial biofilm growth in membrane housing and tubing

PossiblePolyethylene tubing brittleness and microcracking under UV or heat stress

PossibleCross-contamination from improper installation or backflow

Why this gradeBuy

Both products run through the same public rubric: materials, coatings, brand disclosure, lab findings, and recalls, plus a beyond-PFAS hazard analysis. Grades are model-based estimates, not lab tests. How grades work →

More under-sink ro systems: see the full ranking