Waterdrop G3P800 Tankless RO vs PUR PLUS FM-3700B — Which Should You Buy?
Side-by-side comparison of Waterdrop G3P800 Tankless RO and PUR PLUS FM-3700B. We compare specs, performance, and value to help you decide.
Feature Comparison
| Feature | Waterdrop G3P800 Tankless RO | PUR PLUS FM-3700B |
|---|---|---|
| Type | Tankless RO | 2-stage carbon |
| Contaminant Removal | 99.99% | — |
| Capacity | 800 GPD | 100 gallons |
| Waste Ratio | 3:1 | — |
| UV | Yes | — |
| Remineralization | Yes | — |
| Installation | Under sink | Under sink |
| Faucet | Smart display | Included |
| Warranty | 1 year | 90 days |
| Certification | — | NSF |
| Removes | — | Lead, chlorine |
| Filter Life | — | 3 months |
Waterdrop G3P800 Tankless RO
Pros
- ✓99.99% contaminant removal
- ✓UV purification
- ✓800 GPD tankless
- ✓3:1 waste ratio
- ✓Remineralization filter
- ✓No tank needed
- ✓Smart faucet display
Cons
- ✗Premium price
- ✗Requires power
- ✗Complex installation
PUR PLUS FM-3700B
Pros
- ✓Budget-friendly
- ✓NSF certified
- ✓Reduces lead, chlorine
- ✓2-stage
- ✓Simple install
- ✓Dedicated faucet
- ✓Trusted brand
Cons
- ✗Basic filtration
- ✗Doesn't remove fluoride
- ✗Filter life 3 months
Our Verdict
Waterdrop G3P800 Tankless RO
The best overall under-sink filter—premium RO with UV and remineralization for the ultimate in drinking water quality.
20% Off — Limited Time, Check NowPUR PLUS FM-3700B
The best budget under-sink filter—basic NSF-certified filtration at the lowest price.
Limited Offer — Check Today's PriceOur Methodology
We test each under-sink filter for contaminant reduction, installation ease, and long-term cost. No manufacturer has editorial influence.
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