Household cleaners are the "gateway" product for dollar stores, responsible for bringing most shoppers in, Family Dollar spokesman Josh Braverman says. For good reason, too, as most of the basic ingredients in branded and unbranded cleaners are about the same.

Super Window glass cleaner in a 32-ounce bottle was 99 cents (of course) at a 99¢ Only store in Los Angeles. Windex in the same-size bottle was $4.29 at a Vons supermarket down the street.

Awesome Carpet Spot & Stain Remover was 99 cents for a 32-ounce bottle at the dollar store. A 22-ounce bottle of Resolve was $3.54 at a Los Angeles Target store.

"We have concerns about vitamins and some medications sold at dollar stores," says Anthony Giorgianni, the associate editor of Consumer Reports' Money Adviser.

Vitamins are considered dietary supplements by the Food and Drug Administration, so they receive less oversight than drugs do. Several years ago, Consumer Reports found that half of the dollar-store brands it studied contained less of the vitamins than the labels indicated and didn't dissolve properly when ingested. Similar problems weren't found for brand names.

The good news about shampoos and conditioners is that there is no difference in quality between the cheap ones and pricier versions, says "cosmetics cop" Paula Begoun, the author of "Don't Go to the Cosmetics Counter Without Me." There are no ingredients to avoid or worry about, she says. Just don't believe all the claims on the bottles.

Some of the best buys can be found on discontinued product lines. A bottle of Marc Anthony Aroma Organics shampoo that was 99 cents at a Los Angeles dollar store was marked down from $7.45 to $3.74 at a nearby Vons supermarket.

An 11.25-ounce bottle of juicy melon Softsoap was 99 cents at the dollar store. A 7.5-ounce bottle of the same stuff was $2.09 at a Target store in Los Angeles.

In 2007, the Food and Drug Administration warned consumers that many brands of toothpaste found at dollar stores carried diethylene glycol, a poisonous chemical found in antifreeze. Although recalls were issued, some of these products could still be on shelves, including toothpaste made to look like your favorite brands. So, it's probably best to steer clear.

Food can be hit or miss at dollar stores. Though many stores are stocking more bargains on fresh produce and frozen items, not everything is of high quality -- such as cheese made with vegetable oil, says blogger Billy Vasquez, aka "the 99 Cent Chef," who buys recipe ingredients from dollar stores. And much of the freezer selection -- such as giant boxes of frozen corn dogs -- isn't healthful.

Spices, however, are a slam-dunk because they are widely available and at much lower prices than at supermarkets.

A jar of McCormick's paprika cost $4.45 at a Vons supermarket in Los Angeles, but at a nearby dollar store you could get the same amount of paprika for only 99 cents under the Santa Paula label.

Likewise, McCormick's ground thyme cost $7.09 at Vons, but you could buy Santa Paula thyme for 99 cents down the street.

Many dollar-store batteries are the carbon-zinc variety, which drain more quickly and are more sensitive to heat and cold than are traditional alkaline batteries. You'll go through more of them, wiping out any savings, experts say.

Dollar stores are a great place to stock your kitchen with inexpensive utensils, says Anthony Giorgianni, the associate editor of Consumer Reports' Money Adviser. He recently returned a pizza cutter he'd bought for $3 at Target when he found a similar one for a buck at a dollar store. Funnels, whisks, peelers, spatulas and other kitchen tools are also great buys, he says, compared with supermarkets and even discount stores such as Wal-Mart.

Blogger Billy Vasquez, aka "the 99 Cent Chef," even buys his kitchen knives at a dollar store. They may not last as long as Henckels, but he says they cut just fine. However, he's had less luck with dollar-store can openers. "They don't seem to work too well," Vasquez says. "I haven't found a good can opener from a dollar store."

Latex kitchen gloves were just 99 cents at a Los Angeles 99¢ Only store. Down the street, Playtex gloves had a $2.29 sale price at a Vons supermarket.

A stainless-steel potato peeler was just 99 cents at the dollar store versus $4.19 for an Epicura peeler -- the lowest-priced model -- at a Los Angeles Target store.

"We think it's best not to buy anything that you plug in from a dollar store," says Anthony Giorgianni, the associate editor of Consumer Reports' Money Adviser.

Products may not be wired to handle the current they receive. Some also have shoddy insulation around the wiring, which can pose a risk for overheating.

There's going to be little difference in quality between a paper gift bag you buy at a dollar store and one you pick up at your local drugstore. It's just a question of taste. If you can find something that you like at a dollar store, you're going to save a bundle, says Anthony Giorgianni, the associate editor of Consumer Reports' Money Adviser.

Party plates and napkins, as well as birthday signs and party favors, are also great finds. Just don't expect your daughter's favorite licensed character to be printed on them.

A 20-foot roll of Disney Princess wrapping paper cost $3.64 at a Target store in Los Angeles; a 25-foot roll of pink gift wrap with hearts and flowers cost 99 cents at 99¢ Only.

Gift bags of all sizes were 99 cents at the dollar store, compared with 99 cents to $3.99 at Target, depending on size and decoration.

Jewelry and vinyl lunchboxes and have been recalled from dollar stores as dangerous sources of lead. New consumer-products legislation was supposed impose testing and remove this threat from stores, but experts say it's wise not to take chances.

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