Is Tony the Tiger worth his stripes? Maybe not. For about half the price, you can buy a Kellogg's Frosted Flakes imitator that's almost as grrreat.

Our tests of three top-selling cereals showed the same is true of General Mills Cheerios and Kellogg's Frosted Mini-Wheats. When we pitted these big-name products against Malt-O-Meal -- a small, lower-cost brand sold nationwide -- and several private-label knockoffs, we found some that come close to dethroning the kings of the breakfast table.

You may not be familiar with these products. Sales of private-label cereal account for just 10 percent of the market, up 3.8 percent from 2004 to 2005, according to market-research company Mintel. The price gaps between private labels and big brands, meanwhile, can be significant: A box of Kellogg's Frosted Flakes costs $3.38; a box of Kroger Frosted Flakes costs $1.76. Part of the surcharge is the result of advertising and marketing expenditures. There can also be hidden extras, such as fees for prime positioning on supermarket shelves.

Frosted flakes. Is Kellogg's worth the higher cost? Our trained tasters found significant difference between Kellogg's Frosted Flakes and those from Kroger and other private labels, whose cereals were nonetheless judged "good." (Private-label flakes from Albertson's, 15 cents per serving, and Safeway, 18 cents, led that group.) Yet there was less difference between Kellogg's and Malt-O-Meal. Both were rated "very good." At just 13 cents per serving, however, Malt-O-Meal flakes cost about half as much as Kellogg's.

Toasted oats. The "very good" oats from General Mills (Cheerios, at 24 cents per serving), Malt-O-Meal (13 cents) and Stop & Shop (20 cents) tended to have more flavor than the "good" cereals from private labels. Among the better of those oats were products from Trader Joe's (14 cents) and Albertson's (17 cents).

Mini-wheats. Joining Kellogg's (43 cents) as "very good" products in this group were Kroger (20 cents) and Malt-O-Meal (19 cents). They had a clean, balanced flavor and a nice crunch, according to our tasters. Safeway (28 cents) and Target (its Market Pantry mini-wheats cost 20 cents a serving) were the best of the "good" group.

Within their respective categories, products had similar nutritional values, providing about the same amount of calories, fat, sugar and fiber per serving. Malt-O-Meal's Scooters were more sugary than the other toasted oats. All the toasted oats were made with whole grains, which contribute vitamin E, vitamin B, fiber, phytonutrients and minerals -- including iron -- to your diet. Studies have shown that whole grains can help control weight by leaving you feeling fuller. They also may protect against heart disease, diabetes and certain cancers.

To find a product high in whole grains, look for them to be listed as the first ingredient on the package. ("Processed whole grain" has the same nutritional makeup.) Another sign: the Whole Grains Council stamp, which is allowed on products with at least 8 grams per serving. "Refined grain" on a package refers to white flour -- it lacks the nutrients of whole grain -- while "enriched grain" is refined grain with some nutrients returned.