Shopping for a mattress can be a challenge. It's hard to tell one box of metal, foam, and fabric from another, making you vulnerable to a sales pitch.

Model names differ from store to store, making it hard to comparison shop. And prices vary so much that the $1,300 mattress set you look at one day can cost $2,600 the next. The good news: Years of testing have shown that all but the cheapest mattresses are apt to be sturdy. While there is no best bed for everyone, you can learn a lot simply by trying a mattress for 15 minutes.

WHAT'S AVAILABLE

Innerspring mattresses are the most widely sold type. Sealy, Serta, Simmons, and Spring Air are the top-selling brands. Highly hyped alternatives to conventional versions include Duxiana (springs galore, in layers); Select Comfort (air-filled, with adjustable firmness for each partner); and Tempur-Pedic (polyurethane "memory foam"). You'll also find foam- and feather-filled mattress toppers designed to improve a too-hard bed. Price: $500 to more than $5,000 for mattresses; about $70 to $800 or more for queen-sized toppers.

IMPORTANT FEATURES

Most stores have a cutaway or cross-section of at least some mattresses. Here's what matters:

Ticking, the outermost layer, is typically polyester or cotton-polyester, while fancier mattresses may use damask, jersey knit, microsuede, wool, cashmere, or silk. What really counts is the stitching that binds the ticking to the top padding, which affects how the mattress feels. Look for a large quilt pattern if you like a deep, cushioned sensation; smaller patterns tend to create a slightly firmer feel.

Top padding is usually one or more types of polyurethane foam with or without polyester batting, which provides a soft feel and helps dissipate perspiration. In foam layers, latex is soft, supportive, and resilient, while visco-elastic "memory foam" conforms to your body and can help insulate you from feeling motion on the other side of the bed. Convoluted foam ("egg crate") feels softer than a straight slab of the same type of foam.

Coils provide the main support, and all the hyped types "whether Bonnell (in an hourglass shape), continuous wire, or individually pocketed" are up to the task. But heavier-gauge coils can provide a stiffer suspension, and lighter-gauge coils usually lend a springier feel. Some manufacturers beef up certain areas for extra support by using more closely spaced coils, slabs of stiff foam around edges and between coils, or thicker wire. Stiffer edges make for a solid place to sit and tie your shoes, and keep you from feeling as if you'll roll off. Among big-name mattresses with extra-support zones: Simmons BackCare and Sealy BackSaver.

There's nothing springy about box springs, which simply provide support. Manufacturers often deliver the same box spring with various models within their lines, regardless of price. If you buy an ultrathick mattress, consider pairing it with a "low profile" box spring, 4 to 6 inches thick, instead of the usual 10 inches or so, to reduce height.

HOW TO CHOOSE

Once you've settled on the size you need, shop around for the firmness and feel you like. Here's what else to consider while shopping:

Consider an innerspring first. A conventional innerspring mattress is the most common choice and is often the least expensive. Memory foam is heat-sensitive and conforms to your body. Tempur-Pedic is the big name, but there are other brands. Not all memory foam feels the same, and it can take time to get used to. A third option: an inflatable mattress that lets you choose a different firmness for each half of the bed. Select Comfort is the major brand.

Choose a store. Don't buy online or over the phone unless you've already tried the identical model at a store. Department stores have frequent sales and lots of brands. Bedding stores like Sleepy's and 1-800-Mattres, along with furniture stores, offer variety and are often less crowded.

Do the 15-minute test. Lie down on lots of mattresses. Wear loose clothes and shoes you can slip off. And spend at least five minutes on each side and on your back, and some time on your stomach if that's how you sleep.

Win the name game. Manufacturers usually modify innerspring mattresses for different sellers, changing the color, padding, quilting pattern, and so forth, thwarting comparison. Fortunately, a big chain such as Sears or Bloomingdale's typically has the same model names for the same beds at all of its stores, usually at the same price. Some bedmakers provide helpful information on their Web sites. Go to www.simmons.com, for example, and you'll find basics about the company's Beautyrest, Classic, World Class, and Exceptionale lines. All beds in each line share attributes.

Save on the foundation. These can sell for as much as the mattress they're sold with, even though they're generally just a wood frame enclosing stiff wire. Since companies frequently pair the same foundation with mattresses in different price ranges, you may save by buying a higher-priced mattress with a lower-priced foundation. If your current foundation is only a few years old, with no rips, warps, creaks, or "give," consider using it with a new mattress. If the old box has bouncy springs instead of stiff wire, replace it.

Don't overpay for toppers. Price is no harbinger of a good night's sleep. One panelist in our tests found lying on an $890 Tempur-Pedic memory-foam topper akin to sinking in quicksand. We also suggest airing out foam toppers for a day or two to help get rid of the chemical odor some come with. As for feather-filled toppers, even pricier models can shift overnight and make beds look lumpy.

Don't count on warranties. The norm is a 10-year warranty, while Duxiana, Select Comfort, and Tempur-Pedic offer ones for 20 years. But warranties cover only defects in materials and workmanship, not comfort or normal wear. Some don't cover full replacement value. What's more, removing that "do not remove" tag really will void the warranty as readily as if the mattress was soiled or had uneven support from the foundation or frame.

Copyright © 2003-2008 Consumers Union of U.S., Inc.

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