What are you really getting when you purchase a store-brand or private-label beauty product that claims it "compares with" a better-known national brand?

To find out, the Good Housekeeping Research Institute performed blind comparisons in three categories -- anti-aging facial moisturizer, body lotion and two-in-one shampoo/conditioner.

The name-brand face lotion and shampoo/conditioner were both clear winners over their store-brand counterparts.

Panelists preferred the scent and "silky" feel of the name-brand face lotion. Lab analysis also revealed that the name-brand contained anti-aging ingredients that weren't in the imitator.

Volunteers who liked the name-brand two-in-one shampoo/conditioner said it left their hair smoother and more manageable.

Testers were evenly split on which body lotion worked best. Some thought the name brand was better at moisturizing, while others favored the store brand for the same reason.

Here's help in deciding whether to buy store-brand or pony up for the name brand.

Look at the ingredients . "If it's not on the list in the private-label product, that should send your antennae up," said Warren Wallo, director of scientific affairs at Johnson & Johnson.

But even if the ingredients lists are the same, the products might be different. When J&J scientists lab-tested a knockoff face lotion from a mass-retail outlet, they found that the soy ingredient listed was inactive.

Compare the claims . For example, language on a knockoff was more related to enhancing skin's natural glow, whereas the name-brand product can claim it's "clinically proven" to even skin tone.

"You'll be hard-pressed to find a knockoff that's clinically proven to work," said Wallo.

Consider where you'll use it. "I'd stay away from store brands that go on sensitive areas of your body like the face," advised Patricia Farris, a dermatology professor at Tulane University. "Even basic facial cleansers can differ in ways that affect skin."

Stick to store-brand products that deliver instant results . Things that don't need to be used repeatedly to produce a benefit -- such as body lotions and hairsprays -- are the safest bet.

These bargain brands are backed by studies to prove they can outperform their pricier peers:

» Pantene Pro-V Nature Fusion Smooth Vitality Shampoo and Conditioner ($4 each, drugstores). In a blind test, salon-brand users tried these products for two weeks. Sixty-nine percent said they were as good as or better than a salon shampoo and conditioner. The savings was about $18.

» Aveeno Positively Radiant Tinted Moisturizer SPF 30 ($16.59, drugstores). In a comparison with the best-selling department-store tinted moisturizer, participants said Aveeno provided a more natural-looking and radiant finish. Savings was about $25.

» Olay Professional Pro-X Deep Wrinkle Treatment, Age Repair Lotion SPF 30, and Wrinkle Smoothing Cream ($42 each, drugstores). A six-month clinical study of this regimen found it performed as well as the leading prescription 0.02 percent tretinoin wrinkle treatment, reducing the appearance of fine lines and wrinkles by 20 percent. Savings was about $140.

On another matter : In honor of the Good Housekeeping Seal's 100th anniversary, check out these seal holder products with surprising uses. Fresh Step Scoopable (cat litter with odor-eliminating carbon) provides a quick fix for absorbing oil stains on the driveway and better traction on icy days. Bounce and Downy dryer sheets blot up detergent spills after use in a load, thwart a stinky garbage can as a liner and zap static on clothes. Clorox Bleach Pens can clean dingy discoloration on tile grout.