Pricey Duxiana Dux 515 mattress is good not great

The $7,595 Duxiana Dux 515 mattress isn't the most expensive one sold by the luxury mattress maker. But let's put it this way—the Dux 515 costs just a little less than the combined cost of the other seven recommended innerspring mattresses in Consumer Reports tests. With our interest piqued by the price, we purchased the Dux 515 to see how it stacks up against the dozens of innerspring, memory foam, and adjustable air mattresses in our tests. Here are the details.

Anyone spending almost $7,600 for a mattress has every right to expect a good night's sleep. And that's possible with the Duxiana Dux 515 if you sleep on your side. It showed impressive side support in our tests, which measure how well a mattress keeps your spine horizontal when lying on your side. But the Dux 515 is only mediocre if you sleep on your back, according to our tests that measure how well a mattress supports and maintains the spine's natural curve when the sleeper is supine. The best innerspring for back sleepers is the Charles P. Rogers Powercore Estate 5000, $1,500, which got excellent marks in our tests.

One comforting finding about the Dux 515 is that it earned top marks in our durability tests, which simulate eight years of use. So if you buy one, you can at least be assured that it will last. And it was decent at muting vibrations, meaning there's little bouncing from one side of the bed to the other—a plus we didn't find in the $4,800 Duxiana Dux 101.

Duxiana says what's special about the Dux 515 is that it features "individualized personal comfort zones" that allow you to adjust the the amount of support under your shoulders, thighs, and legs. Beneath a replaceable topping of latex foam are six compartments, three per side, that accommodate "spring cassettes." By default, the mattress comes with a pair of firm, medium, and soft. If you want a different combination you'll pay more. You can place the cassettes in the compartments in any order. But no matter how we arranged them in our tests, we judged the firmness of the mattress to be soft and not as firm as the company claims.

Need a new mattress?

The typical mattress seller wants you to believe you have to pay a lot, though not $7,600, for a winning mattress, but our mattress tests have found models that offer consistently impressive or better back and side support for less than $1,100. Examples are the $1,075 Serta Perfect Day iSeries Applause innerspring, Casper's $850 The Casper 10" foam, and the $700 Sleep Number c2 Bed, an adjustable-air mattress. See our online Ratings of almost 40 mattresses, along with companion, survey-based Ratings of mattress stores and brands. And be sure to check out our free buying guide for mattresses before narrowing your choices.

—Ed Perratore (@EdPerratore on Twitter)