Serta iSeries NXG 3500 Medium Foam

All-foam NXG with Ultimate Edge support, medium feel. Serta iSeries NXG 3500 Medium Foam is built around durable base with reinforced perimeter.

Serta sells this model at $2,599 for a queen (list $2,899). That places it at the premium end in the current lineup, which runs from the $499 Classic innerspring up to the $3,599 iComfortPro Level Three. If your budget is fixed, the table above is the fastest way to see what a hundred dollars either direction actually buys you inside the same brand.

The comfort stack is: CoolFeel Plus cover — upgraded cooling cover system; NXG memory foam — high-density memory foam for deep contouring; Transition foam — gradual step-down to the core; High-density foam core with Ultimate Edge — durable base with reinforced perimeter.

In practice, that build gives a medium surface. Couples who hate motion transfer sleepers get the most out of it; combination sleepers will want to look one model up or down the range. Serta's zoned support systems all share the same idea — firmer coils or foam under the hips and lumbar, softer at the shoulders — so moving between models in this lineup changes the comfort layers far more than the support feel.

Serta.com sells this model with a 120-night trial and a 10-year limited warranty, with free shipping. Buying through a retail partner such as Mattress Firm or Costco changes both the trial terms and the price, so confirm the return window at checkout rather than assuming Serta's direct policy applies.

Our 8.5 score is an editorial score. It comes from the published construction, materials and firmness, current per-size pricing, hands-on time with Serta's comfort levels in showrooms, and how the model compares to the rest of the range and to rival brands at the same price. It is not the output of a completed lab protocol on this individual unit, and we say so on every Serta page rather than implying testing we have not done.