Jennifer Wood is on the hunt for a new cake pan. At the Sur La Table store at Pentagon Row, she has her choice of a traditional pan made of aluminum or one made from tomato-red silicone rubber that can be folded up and stored in a corner of a cupboard. But for Wood, it's no contest. She prefers a metal pan to one that might wobble and bend at a crucial moment.

"I've heard a lot about the silicone pans. But there are issues," says Wood, who lives in the District. "Once it's filled with batter, how would you get it from the counter to the oven?"

Over the past several years, silicone, a type of food-grade, synthetic rubber approved by the Food and Drug Administration, has revolutionized the kitchen. Take a look around a local housewares store: There are heat-resistant silicone spatulas in every hue, as well as silicone-coated whisks, basting brushes, rolling pins, ice trays, bowls, funnels, trivets and rubber oven mitts that look like hand puppets. There is even a silicone tortilla warmer.

More recently, housewares companies have introduced lines of silicone bakeware in every shape. Manufacturers say these soft-to-the-touch pans and molds are nonstick, stain-resistant, dishwasher-safe and heat-resistant to temperatures of 450 degrees. Sudden changes in temperature pose no problem. Silicone bakeware can go from the freezer to the oven or -- unlike metal pans -- the microwave. Bakers with limited storage space can tuck them in a drawer.

But sometimes the next great thing is not so great. The lack of stability that Wood cited is one reason consumers pause when considering whether to buy a silicone cake or loaf pan. (Manufacturers encourage placing the pan on a baking sheet for stability.) Favorite recipes might require 10 percent less time in the oven. (Silicone transfers heat differently than metal.) Some of the larger baked goods don't pop right out of silicone pans. (A squirt of nonstick spray oil eases the release.)

Moreover, we found, after testing several brands, that yeasted dough does not rise as well in silicone. And silicone pans cost more than metal pans. (A good, full-size, metal muffin pan costs about $19, while a silicone pan runs around $27.)

Metal bakeware is still the clear favorite with consumers. But NPD Group, a marketing information company, calls silicone bakeware "an important segment of the industry," with 3.6 percent of total bakeware units sold in the 12 months ending in July compared with 0.8 percent of the market during the same period one year earlier. "I don't know if Grandma Smith is going to give up her metal bakeware. But for weddings and young people, this is a promising category," says NPD spokesman Peter Greene.

If the silicone trend has a father, he would be French inventor Guy Demarle. In 1982, Demarle introduced a flexible, silicone baking sheet liner called the Silpat. Pastry chefs swooned when sticky cookies, for example, could easily be removed from the reusable liner. Now nearly every shape and size of baking pan, from loaf to Bundt and beyond, is available in silicone.

SiliconeZone created six silicone kitchen pieces in late 2001 and now makes more than 150. Sales for the firm, one of the largest manufacturers of silicone housewares, have increased from $3 million to $10 million in three years.

"In the beginning," chief executive Michael Karyo says, "a lot of people thought that [silicone products] would only appeal to young people. But it's all over the map."

KitchenAid, a division of Lifetime Brands, launched its line of silicone bakeware in 2003 with 12 styles in two colors, red and blue. In the past two years, it has added 10 pieces as well as specialty sets.

"It's gone through the roof for us," says Karen Sullivan, senior category manager for silicone bakeware. Sullivan says KitchenAid's most popular pieces are the 12- and 24-cup muffin pans that come with a carbon steel wire "sled" that is intended to help with stability when moving the pan in and out of the oven.

Rick Agresta, president of Orka ISI, the company that makes the popular Orka silicone oven mitt, says, "Flexibility is the key reason why people buy silicone." Last year the company produced a 12-piece weighty line of bakeware that, unlike the colorful competition, is solid black. "The marketplace is saturated with colored silicone. But to a lot of people, it doesn't look like bakeware. We wanted a more serious line with different features, such as handle grips," Agresta says.

Mark Ramsdell, head of the professional pastry program at L'Academie de Cuisine, calls silicone "incredibly convenient with multiple uses." But he says the products have limitations. "Silicone will never replace metal totally. There is more precision with, let's say, a tiny fluted edge on a metal mold. You can't get that with silicone. And you have to be careful not to cut them with a knife."

Silicone pans have a big fan on the Eastern Shore. "They are ingenious; incredibly useful for madeleines," says Andrew Evans, chef and co-owner of the Inn at Easton. "The mold supports the cookie as it cooks, and they just pop right out."

Product testing of four silicone brands for the Food section found the pop-out factor of these pans is best realized with desserts that require slow, even heat, such as custards, creme caramel and cheesecake. They are great for ice cream cakes. Small tart pans work well. But the larger the pan, the harder it is to handle when it comes time to flip something out of it.

Muffins and quick breads did not brown on the sides as they would in a metal pan. Any baked goods that require high heat for rising such as yeasted breads are better suited to metal pans. Special correspondent Stephanie Witt Sedgwick contributed to this report.

Le Creuset's Cook 'n Bake line of silicone bakeware, represented here by the 12.5-cup savarin pan, at top right, fared best in our testing of four companies' products. It's lightweight and highly polished on the inside for easy release.