Of the six (6) best consumer reviews for under sink water filter systems identified here, one (1) of them was from the iSpring Water Systems company. I have included a product review for it as well as a table showing how it compares with the top rated Waterdrop filter system.
ISpring US31 Classic 3-Stage Under Sink Water Filter System
Consumer Rating: #3
Price: ~ $113 US
Owner: iSpring Water Systems
Certification: NSF/ANSI Standards 42, 53, and 61
Filtration Method: Stage 1- Sediment, Stage 2 – GAC, Stage 3 – CTO
Filter Capacity: 2000 Gallons or every 6 Months
Filter Cost: ~ $22 US for a 3-pack
Options: Can connect an ice maker kit to the fridge at an extra cost
Warranty: 30-day return policy with Amazon
Other: Includes brushed nickel all-metal faucet and clear see-through 1st stage housing to make filter inspection a snap.
Description: This product was rated 3rd from the list of 6 top rated products as determined by the Consumers. The ISpring US31 adopts a 3-stage filtration method to effectively remove/reduce dust, sand, dust, rust, chlorine, taste and odor, and other harmful chemicals and improves the taste of water in the process. The 3rd Stage includes a 5-micron filter that will remove other unwanted contaminants such as asbestos fibers (particle size = 7 microns). It effectively enhances the potable water from your faucet to bottled water quality saving you hundreds of dollars annually.
Pros: Simple installation, inexpensive filters, excellent product support
Cons: Intended for potable water (i.e. not well water), does not remove fluoride, bacteria, and pesticides if present.
ISpring US31 (#3) to Waterdrop 17UA (#1) Under Sink Water Filter System Product Comparison
| Model | Waterdrop 17UA | ISpring US31 3-Stage |
|---|---|---|
| Filter | Activated carbon made from natural coconut shells | 3 Filters; 1st Stage = Sediment, 2nd Stage = GAC, 3rd Stage = CTO |
| Filter Capacity | 24000 Gallons | 2000 Gallons or 1st Stage = 6 Months, 2nd Stage = 6 Months, 3rd Stage = 6 Months |
| Flow Rate | 0.75 GPM | Up to 1 GPM |
| Chlorine removal | Yes | Yes |
| Lead removal | Yes | No |
| Fluoride removal | No | No |
| Sediment removal | Yes | Yes |
| Heavy Metals removal | Yes | Yes |
| Bacteria/Cysts removal | No | Yes |
| Contaminants > 0.01 uM removal | No | No |
Conclusion
The iSpring US31 was rated 3rd in the top 6 rated products as determined by the Consumer. You can find more about this here. Also, a side-by-side comparison of these 6 products can be found here. They each have their unique features and I hope you find the one that fits your needs the best.