It had been a Behr market since 2003, with the Home Depot brand occupying every top spot but one in Consumer Reports' ratings categories of interior paints. But in CR's latest tests, paints from Benjamin Moore, Kilz and Valspar edged into first place.

Behr hasn't fallen to the bottom of the best interior-paint charts — its flat and semi-gloss paints merit an excellent overall score, and the low-luster a very good. But the passing of the paint stirrer, er, baton is a reminder that paints are in constant flux. Manufacturers tinker with formulas to improve performance, meet environmental regulations and cut costs.

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CR named the following products as CR Best Buys: Among low-luster products: Kilz Casual Colors Satin (Wal-Mart) $19; for flat paints, Behr Premium Plus Enamel (Home Depot) $22; Kilz Casual Colors, $18; and Dutch Boy Home (Wal-Mart), $15; and among semigloss finishes, Dutch Boy Home (Wal-Mart), $18.

The recipe revamping can make it difficult to decipher the lingo and claims consumers see on cans at a home center or paint store: Valspar touts its "Advanced Ti3 Technology," Benjamin Moore reveals its "Authentic ColorLock" system, Dutch Boy promises "Single Coat Application," and Ace pledges "25 Years of Durability."

To help people find the best choice, CR's experts ran dozens of paints through a battery of tests to measure hiding power, stain resistance, surface smoothness and other characteristics. Here's what they found:

Mixed marks for low-VOC finishes. VOCs are solvents in paint that get released into the air as consumers use the finish. They can cause headaches, dizziness and other acute symptoms. The long-term effects are less certain, but, according to the U.S. Environmental Protection Agency, some VOCs used in paints are known or suspected carcinogens.

To help curb ozone pollution, the federal government caps the VOC content of paint at 250 grams per liter for flat finishes and 380 grams per liter for others. The knock against the first low-VOC paints was that they lacked the durability and the sheen selection of higher-VOC finishes. (No zero-VOC paints CR tested most recently were highly rated.) But companies now make top-quality lower-VOC paint. High-scoring Benjamin Moore Aura, True Value Easy Care and Glidden Evermore low-luster products contain less than 50 grams per liter of VOCs. Look for the VOC level on cans.

Bright spots for fade resistance. Fading has long been a problem, resulting in walls that get lighter over time as they're exposed to sunlight. But manufacturers appear to be improving the fade resistance of their paints. More than half the products CR tested in the best interior paints reviewed deliver good or better protection.

One-coat options expand. CR's testers identified 14 paints that are good or better at covering a contrasting color with one coat, up from nine in CR's last report.

How to choose

Avoid blind product loyalty. CR's latest tests reveal that always buying the same paint might not be a wise choice. The Brand X finish consumers loved the last time they painted is probably not the same as what's on shelves today.

Consult www.ConsumerReports.org for ratings on interior paints to make sure that a former favorite finish still shines.

Consider the gloss. Flat paints hide imperfections but are not the most stain resistant, so they're best in decorative settings, such as a living room or dining room. High-sheen semigloss paints are easy to clean, but their gloss can change, so use them on trim, windows and doors. Low-luster paints generally combine the best of both categories, resulting in an all-around durable paint that's easy to clean.

Think quality, not quantity. Always consider top-of-the-line products. Factoring in the real cost of painting, which includes materials, labor costs and life span, a paint that endures for 10 years will set people back less than one that lasts half that time. Consumers won't have to travel far for premium paint. Products sold at Home Depot (Behr), Lowe's (Valspar) and Wal-Mart (Kilz) are among CR's top performers.

Write to: Consumer Reports, 200 Madison Ave., New York, NY 10016; on the Web at www.consumerreports.org.