Frizzlife PD800-TAM4
#12 in TanklessFull review
For a household that wants fast mineralized RO water with low filter costs and does not need NSF 58 certification.
Amazon $509.98$509.98
The Frizzlife PD800-TAM4 and the iSpring RO800G are evenly matched, rated 3.1 and 3.0. The Frizzlife PD800-TAM4 leads on certification. The iSpring RO800G wins on filter cost and price. The iSpring RO800G costs $50.99 less ($458.99 vs $509.98).
iSpring RO800G
#14 in TanklessFull review
For big households that want fast tankless RO with low waste and cheap filters. It lacks the third-party certification of pricier rivals.
Amazon $458.99$458.99
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 Frizzlife PD800-TAM4 for certification (not certified to NSF/ANSI 58; certified to NSF/ANSI 372 vs no third-party certification).
- Choose the iSpring RO800G for filter cost ($85 a year in replacement filters vs $119 a year in replacement filters) and price ($458.99 vs $509.98).
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 | Frizzlife PD800-TAM4 | iSpring RO800G |
|---|---|---|
| Overall rating | 3.1/5 | 3.0/5 |
| Certification 25% | 30 not certified to NSF/ANSI 58; certified to NSF/ANSI 372 | 0 no third-party certification |
| Filter cost 20% | 46 $119 a year in replacement filters | 67 $85 a year in replacement filters |
| Water wasted 15% | 95 2:1 pure to drain | 98 2.5:1 pure to drain |
| Output 10% | 71 800 gallons a day | 71 800 gallons a day |
| Price 15% | 44 $509.98 | 53 $458.99 |
| Warranty 15% | 0 warranty not published, scored as none | 0 1-year warranty |
Specifications
| Frizzlife PD800-TAM4 | iSpring RO800G | |
|---|---|---|
| Filtration | ||
| Output | 800 gallons a day | 800 gallons a day |
| Pure to drain | 2:1 | 2.5:1 |
| Stages | 9 | 2 |
| Remineralization | Yes | No |
| NSF/ANSI 58 | No | No |
| Other certifications | NSF/ANSI 372 | - |
| Replacement filters | $119 a year | $85 a year |
| Build | ||
| Tank | Tankless | Tankless |
| Booster pump | Yes | Yes |
| Smart faucet | Yes | No |
| Warranty | - | 1 year |