Waterdrop G5P700A
#2 in TanklessFull review
For a buyer who wants certified RO with mineralized water and a smart faucet for around $300.
Amazon $309.99$309.99
The Waterdrop G5P700A is the better under-sink reverse osmosis system overall, rated 3.8 to 3.2. The Waterdrop G5P700A leads on price and filter cost. The Aquasana HealthShield RO wins on warranty and output. The Waterdrop G5P700A costs $990 less ($309.99 vs $1,299.99).
Aquasana HealthShield RO
#9 in TanklessFull review
For a buyer who wants the broadest certification in a fast tankless system and doesn’t mind the price. Most households get similar output for much less elsewhere.
Amazon $1,299.99$1,299.99
Prices were last checked November 2, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the Waterdrop G5P700A for price ($309.99 vs $1,299.99) and filter cost ($130 a year in replacement filters vs $350 a year in replacement filters).
- Choose the Aquasana HealthShield RO for warranty (2-year warranty vs 1-year warranty) and output (800 gallons a day vs 700 gallons a day).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every tankless under-sink reverse osmosis system; a clear win is highlighted. How we rank explains each one.
| Factor weight | Waterdrop G5P700A | Aquasana HealthShield RO |
|---|---|---|
| Overall rating | 3.8/5 | 3.2/5 |
| Certification 25% | 100 certified to NSF/ANSI 58 | 100 certified to NSF/ANSI 58 |
| Filter cost 20% | 41 $130 a year in replacement filters | 0 $350 a year in replacement filters |
| Water wasted 15% | 95 2:1 pure to drain | 94 1.8:1 pure to drain |
| Output 10% | 57 700 gallons a day | 71 800 gallons a day |
| Price 15% | 83 $309.99 | 0 $1,299.99 |
| Warranty 15% | 0 1-year warranty | 25 2-year warranty |
Specifications
| Waterdrop G5P700A | Aquasana HealthShield RO | |
|---|---|---|
| Filtration | ||
| Output | 700 gallons a day | 800 gallons a day |
| Pure to drain | 2:1 | 1.8:1 |
| Stages | 8 | 2 |
| Remineralization | Yes | No |
| NSF/ANSI 58 | Yes | Yes |
| Other certifications | NSF/ANSI 372 | NSF/ANSI 42, 53, 372, 401 |
| Replacement filters | $130 a year | $350 a year |
| Build | ||
| Tank | Tankless | Tankless |
| Booster pump | Yes | - |
| Smart faucet | Yes | No |
| Warranty | 1 year | 2 years |