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Yawnder Reviews · Specifications and prices checked October 7, 2026
Research & editorial review
Serta iSeries NXG Foam Review (2026): All 4 Models Compared
Serta lists four current iSeries NXG foam models alongside four hybrids. The shared name and blue presentation can make them easy to mix up. These foam versions use a foam support core and Ultimate Edge support rather than the Q4 spring unit. That is the most important first decision, before comparing model numbers or cooling materials.
Compare the full Serta lineup in our Serta mattress hub.
Quick verdict
NXG Foam is for a contouring, spring-free preference. Choose 1500 Firm, 2500 Plush, 3500 Medium, or 4500 Ultra Plush according to the feel you want. The model number is not a firm-to-soft sequence, and the Hybrid branch is a different construction.
Reasons to consider it
- Four clearly identified current foam models
- Firm, Medium, Plush, and Ultra Plush choices
- Spring-free alternative within the NXG family
- Selected upper models list split-head sizes
What to weigh carefully
- No current Yawnder test measurements for these models
- Higher tier does not consistently mean softer or firmer
- Comfort-material names do not verify exact foam densities
- Foam edge support needs testing on the selected build
Current models and firmness choices
The model/tier and the selected feel belong together. The summaries below evaluate the current listed builds from manufacturer specifications; they are not a claim that every configuration has been sleep-tested at Yawnder.
iSeries NXG 1500 Firm Foam
1500 Firm Foam is the most structured named foam choice. Serta lists NXG memory foam, carbon-fiber memory foam, Balanced Support Foam, and a high-density support core with Ultimate Edge support. It is the first comparison for a Firm preference and the lowest current Queen price in this branch.
Current listed feels: Luxury Firm. Queen: $2,199.
iSeries NXG 2500 Plush Foam
2500 Plush Foam adds EverCool Plus memory foam and targets a softer surface. It is worth comparing for side sleeping when Firm produces too little shoulder give. A shopper who spends much of the night on the stomach should check pelvic alignment carefully instead of treating Plush as a universally comfortable upgrade.
Current listed feels: Plush. Queen: $2,499.
iSeries NXG 3500 Medium Foam
3500 Medium Foam adds Deep Reaction gel memory foam and the CoolFeel Plus package. Its Medium label makes it the central mixed-preference comparison, even though it has a higher model number than the Plush 2500. Serta lists split-head Queen and King alongside regular sizes; confirm the selected base and mattress geometry together.
Current listed feels: Medium. Queen: $2,899.
iSeries NXG 4500 Ultra Plush Foam
4500 Ultra Plush Foam is the most cushioned named option, with EverCool Supreme memory foam and the CoolFeel Plus package. It is a deliberate choice for a deep-contouring preference, rather than a default recommendation for every sleeper. Compare it with 2500 Plush for the actual comfort benefit of the higher-priced stack.
Current listed feels: Ultra Plush. Queen: $3,199.
Construction and expected feel
All four list high-density NXG memory foam, carbon-fiber memory foam, and a high-density foam support core. The 1500 also identifies Balanced Support Foam. The 2500 adds EverCool Plus memory foam; the 3500 includes Deep Reaction gel memory foam and the CoolFeel Plus package; the 4500 uses EverCool Supreme memory foam with the Plus cooling package. Those are manufacturer material descriptions, not independent density measurements from Yawnder.
The named firmness is not ordered by tier. Firm 1500 targets a more structured contouring experience; Plush 2500 is softer by name; Medium 3500 sits between those preferences; Ultra Plush 4500 is the most cushioned label. An all-foam support system can create a different movement experience from the hybrids. We have not measured recovery speed or firmness on these current builds.
| Specification | Verified scope |
|---|---|
| Construction | Memory-foam mattress |
| Current model/tier entries | 4 |
| Queen listed price range | $2,199–$3,199 |
| Evidence | Manufacturer specifications, current retailer listing, and editorial analysis; no new standardized performance score |
Which sleepers should compare it?
| Sleeper | How to choose |
|---|---|
| Side sleepers | Compare Medium and softer options for shoulder and hip cushioning. Check that the waist and pelvis remain supported; a Plush label alone is not enough. |
| Back sleepers | Start with a balanced Medium or Firm where offered. Check support through the lower back and avoid a top that lets the pelvis sink much farther than the upper body. |
| Stomach sleepers | Compare the firmer available builds. A thick, soft pillow top deserves particular care if it allows the hips to drop. |
| Combination sleepers | Test turning through your usual positions. Comfort-layer depth and the selected firmness can matter as much as whether the mattress has coils. |
| Different body sizes | The same mattress can feel different to lighter and heavier people. Check shoulder pressure, hip support, and edge use on the exact configuration; we have not established a tested weight cutoff for this current family. |
Cooling, movement, and couple considerations
Cooling
Carbon-fiber memory foam and CoolFeel fabrics are intended to redistribute heat and provide a cool surface. The upper two models list CoolFeel Plus. We would not infer a specific overnight temperature drop from those names. If you are sensitive to heat, evaluate how much your body sinks into the selected feel and how your protector and bedding change the surface.
Couples, movement, and edges
A spring-free memory-foam build is a reasonable candidate for shoppers prioritizing a quiet, contouring surface, but no current motion-isolation or edge-load result is available here. Test whether both partners can move easily and use the edge comfortably. The Ultra Plush's added cushioning may appeal to one person while making another prefer the Firm or Medium alternative.
Current Queen prices and value
| Model / tier | Queen configuration | Listed Queen price | Serta checkout status |
|---|---|---|---|
| Luxury Firm | $2,199 | Listed available | |
| Plush | $2,499 | Listed available | |
| Medium | $2,899 | Listed available | |
| Ultra Plush | $3,199 | Listed available |
Exact Queen variants checked in Serta’s official online store on October 7, 2026. These are listed mattress-only prices, not a claim about a future promotion; checkout, retailer pricing, tax, and inventory can change. Photos are manufacturer images.
When the upgrade makes sense
The Queen price ladder matches the hybrid range at the corresponding tier in the verified data, which makes construction a real choice rather than a default saving. Compare 1500 Foam with 1500 Hybrid when you want Firm, and compare the Medium 3500 branches when you want a similar named feel with different support units. Spending more on foam depth is useful only if that specific surface suits you.
Trial, warranty, delivery, and retailer terms
Direct purchases from Serta.com are described on the current product pages with a 100-night trial and a 10-year limited warranty. Serta recommends at least 30 days to adjust before initiating a comfort return. Warranty coverage addresses qualifying defects, rather than guaranteeing that you will prefer a firmness for ten years.
Serta’s current traditional-mattress product pages describe in-home delivery and old-mattress removal for qualifying direct purchases. Confirm the actual delivery date, access requirements, and removal eligibility on your order.
Retailer policies can differ. Get any exchange fee, return fee, required protector purchase, delivery charge, and final-sale restriction in writing before checkout. A manufacturer’s direct trial is not automatically the policy for a purchase from another store.
For a Yawnder purchase, use the terms on your order and our return policy. Contact the Encinitas showroom before visiting to confirm which brands and exact models are on display.
Related Serta reviews and alternatives
Compare the material and surface preference before comparing the tier number. These nearby Serta families offer different ways to solve the same buying decision.
- Serta iSeries NXG Hybrid — Memory-foam hybrid.
- Serta iComfort — Memory-foam mattress.
- Serta iComfortPro — All-foam mattress with latex comfort layers.
Return to the complete Serta model guide or compare Serta with Sealy.
Common questions
Are NXG Foam and NXG Hybrid the same mattress with different names?
No. NXG Foam uses a foam support core and Ultimate Edge support. NXG Hybrid uses Q4 zoned spring support with BestEdge, and selected hybrid tiers add micro coils. Match the construction as well as the model number.
Does this review include a current hands-on test?
This is a research and editorial evaluation of the current manufacturer-listed builds. Product materials, exact variants, prices, and shopping considerations are identified separately from Yawnder’s standardized testing. We do not assign new numeric scores without a test record for the exact configuration.
Which firmness should I choose?
Start with your usual sleep positions, your body size, and how much surface contouring you prefer. Compare the actual listed feel rather than choosing from a tier number or mattress height. Use the sleeper-fit table above, then test the exact configuration or confirm the seller’s trial terms.
Can it work with an adjustable base?
Serta lists adjustable-base compatibility on these product pages. Confirm the exact mattress size and selected base, particularly for split-head sizes, and follow the support and foundation requirements supplied with the mattress.
Can I try it at Yawnder?
Contact our Encinitas showroom before visiting to confirm which brands and exact models are on display. Inventory and display selection can change; a published review is not a guarantee that a mattress is currently on the floor.
Disclosure: Yawnder is a mattress retailer and publisher. We may earn a commission if you buy through our Serta shopping link. Specifications and product photographs are from Serta; the buying analysis is editorial. Affiliate disclosure.
Check the live offer
Promotions change. Use the current brand offer and one last side-by-side check before you order.
Compare this mattress against 142 tested mattresses
Sort all 142 mattresses we have tested by pressure relief, support, cooling, motion isolation, edge support, price, trial and warranty, then filter by how you actually sleep. Of those, 86 hold a complete standardized record and 46 a partial standardized record.